2,107

Recently Sold Frederick, MD Homes

Section Image Section Image
  • 8040 Captains Ct, Frederick, MD 21701
    8040 Captains Ct, Frederick, MD 21701
    /2

    $420,000 Sold Apr 10, 2026

    8040 Captains Ct, Frederick, MD 21701

    • 3 Beds
    • 3.5 Baths
    • 2,404 Sq Ft
    • Built 1996

    Last Sold Summary

    • 3% Below List Price
    • $175/SF
    • 16 Days On Market

    Current Estimated Value $422,210

    Last Listing Agent Adam Iobst A-Team Realty, LLC

    8040 Captains Ct, Frederick, MD 21701
  • 1315 Marsalis Place, Frederick, MD 21702
    1315 Marsalis Place, Frederick, MD 21702
    1315 Marsalis Place, Frederick, MD 21702
    /22

    $440,000 Sold Dec 30, 2025

    1315 Marsalis Place, Frederick, MD 21702

    • 3 Beds
    • 2.5 Baths
    • 1,736 Sq Ft
    • Built 2020

    Last Sold Summary

    • $253/SF
    • 2 Days On Market

    Current Estimated Value $444,022

    Last Listing Agent Stefanie Ventura-Benitez HomeSmart

    1315 Marsalis Place, Frederick, MD 21702
  • 9113 Ridgefield Ln, Frederick, MD 21701
    9113 Ridgefield Ln, Frederick, MD 21701
    9113 Ridgefield Ln, Frederick, MD 21701
    /29

    $411,000 Sold Mar 31, 2026

    9113 Ridgefield Ln, Frederick, MD 21701

    • 3 Beds
    • 3.5 Baths
    • 2,014 Sq Ft
    • Built 1991

    Last Sold Summary

    • $204/SF
    • 85 Days On Market

    Current Estimated Value $415,449

    Last Listing Agent SEAN PERKINS Knot6 Real Estate Services

    9113 Ridgefield Ln, Frederick, MD 21701
  • 2174 Ambleside Ct, Frederick, MD 21702
    2174 Ambleside Ct, Frederick, MD 21702
    2174 Ambleside Ct, Frederick, MD 21702
    /39

    $510,000 Sold Dec 19, 2025

    2174 Ambleside Ct, Frederick, MD 21702

    • 4 Beds
    • 2.5 Baths
    • 2,312 Sq Ft
    • Built 1989

    Last Sold Summary

    • $221/SF
    • 41 Days On Market

    Current Estimated Value $511,398

    Last Listing Agent Melanie Cooley Samson Properties

    2174 Ambleside Ct, Frederick, MD 21702
  • 9232 Landon House Way, Frederick, MD 21704
    9232 Landon House Way, Frederick, MD 21704
    9232 Landon House Way, Frederick, MD 21704
    /44

    $470,000 Sold Sep 26, 2025

    9232 Landon House Way, Frederick, MD 21704

    • 3 Beds
    • 2.5 Baths
    • 2,617 Sq Ft
    • Built 2015

    Last Sold Summary

    • $180/SF
    • 18 Days On Market

    Current Estimated Value $476,907

    Last Listing Agent Henryk Palmer RLAH @properties

    9232 Landon House Way, Frederick, MD 21704
  • 480 Ensemble Way, Frederick, MD 21701
    480 Ensemble Way, Frederick, MD 21701
    480 Ensemble Way, Frederick, MD 21701
    /45

    $759,990 Sold Dec 24, 2025

    480 Ensemble Way, Frederick, MD 21701

    • 4 Beds
    • 3 Baths
    • 3,245 Sq Ft
    • Built 2025

    Move in Ready Sold Summary

    • $234/SF
    • 35 Days On Market

    D.R. Horton Renn Quarter - Single Family

    480 Ensemble Way, Frederick, MD 21701
  • 3019 Stoners Ford Way, Frederick, MD 21701
    3019 Stoners Ford Way, Frederick, MD 21701
    3019 Stoners Ford Way, Frederick, MD 21701
    /36

    $558,000 Sold Jul 02, 2025

    3019 Stoners Ford Way, Frederick, MD 21701

    • 4 Beds
    • 3.5 Baths
    • 3,007 Sq Ft
    • Built 2012

    Last Sold Summary

    • $186/SF
    • 32 Days On Market

    Current Estimated Value $577,447

    Last Listing Agent Joan Reilly Coldwell Banker Realty

    3019 Stoners Ford Way, Frederick, MD 21701
  • 5220 Earles Ct, Frederick, MD 21703
    5220 Earles Ct, Frederick, MD 21703
    5220 Earles Ct, Frederick, MD 21703
    /49

    $399,900 Sold Sep 10, 2025

    5220 Earles Ct, Frederick, MD 21703

    • 3 Beds
    • 3.5 Baths
    • 1,960 Sq Ft
    • Built 1992

    Last Sold Summary

    • $204/SF
    • 10 Days On Market

    Current Estimated Value $406,443

    Last Listing Agent Daisy Price Berkshire Hathaway HomeServices PenFed Realty

    5220 Earles Ct, Frederick, MD 21703
  • 3028 Sanctuary Ln, Frederick, MD 21701
    3028 Sanctuary Ln, Frederick, MD 21701
    3028 Sanctuary Ln, Frederick, MD 21701
    /80

    $485,000 Sold Jan 23, 2026

    3028 Sanctuary Ln, Frederick, MD 21701

    • 3 Beds
    • 3.5 Baths
    • 2,888 Sq Ft
    • Built 2005

    Last Sold Summary

    • $168/SF
    • 5 Days On Market

    Current Estimated Value $488,950

    Last Listing Agent Beth Ohler J&B Real Estate

    3028 Sanctuary Ln, Frederick, MD 21701
  • 335 Ensemble Way, Frederick, MD 21701
    335 Ensemble Way, Frederick, MD 21701
    335 Ensemble Way, Frederick, MD 21701
    /24

    $569,990 Sold Aug 27, 2025

    335 Ensemble Way, Frederick, MD 21701

    • 4 Beds
    • 3.5 Baths
    • 2,270 Sq Ft
    • Built 2025

    Last Sold Summary

    • $251/SF
    • 0 Days On Market

    Last Listing Agent Justin Wood D.R. Horton Realty of Virginia, LLC

    335 Ensemble Way, Frederick, MD 21701
  • 5934 Forum Square, Frederick, MD 21703
    5934 Forum Square, Frederick, MD 21703
    5934 Forum Square, Frederick, MD 21703
    /46

    $422,500 Sold Sep 04, 2025

    5934 Forum Square, Frederick, MD 21703

    • 3 Beds
    • 2.5 Baths
    • 2,498 Sq Ft
    • Built 2021

    Last Sold Summary

    • $169/SF
    • 82 Days On Market

    Current Estimated Value $430,810

    Last Listing Agent Benjamin McCullough Corner House Realty

    5934 Forum Square, Frederick, MD 21703
  • 56 Apple Way, Frederick, MD 21703
    56 Apple Way, Frederick, MD 21703
    56 Apple Way, Frederick, MD 21703
    /14

    $252,002 Sold Mar 19, 2026

    56 Apple Way, Frederick, MD 21703

    • 4 Beds
    • 4 Baths
    • 1,802 Sq Ft
    • Built 1976

    Last Sold Summary

    • 8% Below List Price
    • $140/SF
    • 4 Days On Market

    Current Estimated Value $311,449

    Last Listing Agent Gabriela Vasco Realty Advantage of Maryland LLC

    56 Apple Way, Frederick, MD 21703
  • 329 S Market St, Frederick, MD 21701
    329 S Market St, Frederick, MD 21701
    329 S Market St, Frederick, MD 21701
    /48

    $525,000 Sold Aug 13, 2025

    329 S Market St, Frederick, MD 21701

    • 3 Beds
    • 2.5 Baths
    • 1,867 Sq Ft
    • Built 1865

    Last Sold Summary

    • $281/SF
    • 56 Days On Market

    Current Estimated Value $538,126

    Last Listing Agent Andrew Hopley Keller Williams Realty Centre

    329 S Market St, Frederick, MD 21701
  • 3656 Tavistock Rd, Frederick, MD 21704
    3656 Tavistock Rd, Frederick, MD 21704
    3656 Tavistock Rd, Frederick, MD 21704
    /53

    $660,000 Sold May 07, 2025

    3656 Tavistock Rd, Frederick, MD 21704

    • 4 Beds
    • 4.5 Baths
    • 3,069 Sq Ft
    • Built 2003

    Last Sold Summary

    • $215/SF
    • 24 Days On Market

    Current Estimated Value $651,860

    Last Listing Agent John Bayley Keller Williams Realty Centre

    3656 Tavistock Rd, Frederick, MD 21704
  • 518 N Bentz St, Frederick, MD 21701
    518 N Bentz St, Frederick, MD 21701
    518 N Bentz St, Frederick, MD 21701
    /43

    $655,000 Sold Oct 08, 2025

    518 N Bentz St, Frederick, MD 21701

    • 5 Beds
    • 4.5 Baths
    • 2,840 Sq Ft
    • Built 2016

    Last Sold Summary

    • $231/SF
    • 68 Days On Market

    Current Estimated Value $649,289

    Last Listing Agent Nancy Osborne EXP Realty, LLC

    518 N Bentz St, Frederick, MD 21701
  • 336 Hammersmith Cir, Frederick, MD 21702
    336 Hammersmith Cir, Frederick, MD 21702
    336 Hammersmith Cir, Frederick, MD 21702
    /40

    $450,000 Sold Aug 28, 2025

    336 Hammersmith Cir, Frederick, MD 21702

    • 3 Beds
    • 2.5 Baths
    • 1,626 Sq Ft
    • Built 2023

    Last Sold Summary

    • $277/SF
    • 4 Days On Market

    Current Estimated Value $463,008

    Last Listing Agent Lauren Olson RE/MAX Results

    336 Hammersmith Cir, Frederick, MD 21702
  • 144 Crosstimber Way, Frederick, MD 21702
    144 Crosstimber Way, Frederick, MD 21702
    144 Crosstimber Way, Frederick, MD 21702
    /20

    $605,000 Sold Apr 20, 2026

    144 Crosstimber Way, Frederick, MD 21702

    • 4 Beds
    • 3.5 Baths
    • 3,042 Sq Ft
    • Built 1999

    Last Sold Summary

    • 1% Above List Price
    • $199/SF
    • 14 Days On Market

    Current Estimated Value $595,132

    Last Listing Agent Ken Abramowitz RE/MAX Town Center

    144 Crosstimber Way, Frederick, MD 21702
  • 1402 Timberwolf Dr, Frederick, MD 21703
    1402 Timberwolf Dr, Frederick, MD 21703
    1402 Timberwolf Dr, Frederick, MD 21703
    /40

    $540,000 Sold Aug 21, 2025

    1402 Timberwolf Dr, Frederick, MD 21703

    • 4 Beds
    • 2.5 Baths
    • 2,350 Sq Ft
    • Built 1996

    Last Sold Summary

    • $230/SF
    • 15 Days On Market

    Current Estimated Value $567,618

    Last Listing Agent Anne Boone Keller Williams Realty Centre

    1402 Timberwolf Dr, Frederick, MD 21703
  • 5862 Imperial Dr, Frederick, MD 21703
    5862 Imperial Dr, Frederick, MD 21703
    5862 Imperial Dr, Frederick, MD 21703
    /32

    $405,000 Sold Nov 06, 2025

    5862 Imperial Dr, Frederick, MD 21703

    • 3 Beds
    • 4 Baths
    • 2,100 Sq Ft
    • Built 2018

    Last Sold Summary

    • $193/SF
    • 10 Days On Market

    Current Estimated Value $413,437

    Last Listing Agent Dylan Babra Keller Williams Realty

    5862 Imperial Dr, Frederick, MD 21703
  • 461 Ensemble Way, Frederick, MD 21701
    461 Ensemble Way, Frederick, MD 21701
    /2

    $696,990 Sold Mar 27, 2026

    461 Ensemble Way, Frederick, MD 21701

    • 5 Beds
    • 5 Baths
    • 3,213 Sq Ft
    • Built 2026

    Last Sold Summary

    • 5% Below List Price
    • $217/SF
    • 54 Days On Market

    Current Estimated Value $700,143

    Last Listing Agent Justin Wood D.R. Horton Realty of Virginia, LLC

    461 Ensemble Way, Frederick, MD 21701
  • 7193 W Sundown Ct, Frederick, MD 21702
    7193 W Sundown Ct, Frederick, MD 21702
    7193 W Sundown Ct, Frederick, MD 21702
    /46

    $675,000 Sold Feb 27, 2026

    7193 W Sundown Ct, Frederick, MD 21702

    • 4 Beds
    • 3.5 Baths
    • 2,877 Sq Ft
    • Built 1984

    Last Sold Summary

    • 8% Above List Price
    • $235/SF
    • 2 Days On Market

    Current Estimated Value $647,592

    Last Listing Agent Bill Kauffman Corner House Realty

    7193 W Sundown Ct, Frederick, MD 21702
  • 1511 Bowers Park, Frederick, MD 21702
    1511 Bowers Park, Frederick, MD 21702
    /2

    $6,651,750 Sold May 19, 2025

    1511 Bowers Park, Frederick, MD 21702

    • Land
    • 26 Acres
    • $255,837 per Acre

    Last Sold Summary

    • 59 Days On Market

    Last Listing Agent Jeff Stein Tranzon Key

    1511 Bowers Park, Frederick, MD 21702
  • 2278 Marcy Dr, Frederick, MD 21702
    2278 Marcy Dr, Frederick, MD 21702
    /2

    $424,740 Sold Jul 28, 2025

    2278 Marcy Dr, Frederick, MD 21702

    • 3 Beds
    • 3 Baths
    • 2,353 Sq Ft
    • Built 2025

    Move in Ready Sold Summary

    • $181/SF
    • 9 Days On Market

    2278 Marcy Dr, Frederick, MD 21702
  • 10140A Lenhart Rd, Frederick, MD 21701
    10140A Lenhart Rd, Frederick, MD 21701
    10140A Lenhart Rd, Frederick, MD 21701
    /47

    $849,900 Sold Nov 26, 2025

    10140A Lenhart Rd, Frederick, MD 21701

    • 4 Beds
    • 3 Baths
    • 3,018 Sq Ft
    • Built 1900

    Last Sold Summary

    • $282/SF
    • 7 Days On Market

    Current Estimated Value $858,721

    Last Listing Agent Michael Lederman Compass

    10140A Lenhart Rd, Frederick, MD 21701
  • 5388 Siri Ct, Frederick, MD 21703
    5388 Siri Ct, Frederick, MD 21703
    5388 Siri Ct, Frederick, MD 21703
    /17

    $563,948 Sold Mar 03, 2026

    5388 Siri Ct, Frederick, MD 21703

    • 4 Beds
    • 3.5 Baths
    • 2,205 Sq Ft
    • Built 2026

    Move in Ready Sold Summary

    • $256/SF
    • 22 Days On Market

    Current Estimated Value $560,572

    DRB Homes Park Place Townhomes

    5388 Siri Ct, Frederick, MD 21703
  • 426 N Bentz St, Frederick, MD 21701
    426 N Bentz St, Frederick, MD 21701
    426 N Bentz St, Frederick, MD 21701
    /37

    $280,000 Sold Jan 09, 2026

    426 N Bentz St, Frederick, MD 21701

    • 2 Beds
    • 1.5 Baths
    • 1,089 Sq Ft
    • Built 1895

    Last Sold Summary

    • $257/SF
    • 6 Days On Market

    Current Estimated Value $295,657

    Last Listing Agent Buzz Mackintosh Mackintosh, Inc.

    426 N Bentz St, Frederick, MD 21701
  • 6311 Edgeware Ct, Frederick, MD 21703
    6311 Edgeware Ct, Frederick, MD 21703
    6311 Edgeware Ct, Frederick, MD 21703
    /69

    $640,000 Sold Jun 06, 2025

    6311 Edgeware Ct, Frederick, MD 21703

    • 4 Beds
    • 3.5 Baths
    • 3,220 Sq Ft
    • Built 1999

    Last Sold Summary

    • $199/SF
    • 3 Days On Market

    Current Estimated Value $651,253

    Last Listing Agent Martina Brewbaker Long & Foster Real Estate, Inc.

    6311 Edgeware Ct, Frederick, MD 21703
  • 2367 Bear Den Rd, Frederick, MD 21701
    2367 Bear Den Rd, Frederick, MD 21701
    2367 Bear Den Rd, Frederick, MD 21701
    /58

    $525,000 Sold Jan 12, 2026

    2367 Bear Den Rd, Frederick, MD 21701

    • 3 Beds
    • 2 Baths
    • 1,607 Sq Ft
    • Built 1995

    Last Sold Summary

    • $327/SF
    • 2 Days On Market

    Current Estimated Value $513,933

    Last Listing Agent Jim Bass Real Estate Teams, LLC

    2367 Bear Den Rd, Frederick, MD 21701
  • 1405 Dagerwing Place, Frederick, MD 21703
    1405 Dagerwing Place, Frederick, MD 21703
    1405 Dagerwing Place, Frederick, MD 21703
    /54

    $592,500 Sold Oct 31, 2025

    1405 Dagerwing Place, Frederick, MD 21703

    • 4 Beds
    • 2.5 Baths
    • 2,958 Sq Ft
    • Built 1994

    Last Sold Summary

    • $200/SF
    • 64 Days On Market

    Current Estimated Value $606,485

    Last Listing Agent Suzanne Marsh Marsh Realty

    1405 Dagerwing Place, Frederick, MD 21703
  • 1310 Pedigree St, Frederick, MD 21702
    1310 Pedigree St, Frederick, MD 21702
    1310 Pedigree St, Frederick, MD 21702
    /79

    $440,000 Sold Mar 23, 2026

    1310 Pedigree St, Frederick, MD 21702

    • 3 Beds
    • 2.5 Baths
    • 1,800 Sq Ft
    • Built 2022

    Last Sold Summary

    • $244/SF
    • 21 Days On Market

    Current Estimated Value $436,246

    Last Listing Agent John Heydon Mackintosh, Inc.

    1310 Pedigree St, Frederick, MD 21702
  • 453 Ensemble Way, Frederick, MD 21701
    453 Ensemble Way, Frederick, MD 21701
    453 Ensemble Way, Frederick, MD 21701
    /34

    $789,990 Sold Sep 11, 2025

    453 Ensemble Way, Frederick, MD 21701

    • 6 Beds
    • 5 Baths
    • 3,112 Sq Ft
    • Built 2025

    Move in Ready Sold Summary

    • $254/SF
    • 8 Days On Market

    D.R. Horton Renn Quarter - Single Family

    453 Ensemble Way, Frederick, MD 21701
  • 2505 Coach House Way Unit 3D, Frederick, MD 21702
    2505 Coach House Way Unit 3D, Frederick, MD 21702
    /2

    $299,000 Sold Mar 03, 2026

    2505 Coach House Way Unit 3D, Frederick, MD 21702

    • 2 Beds
    • 2 Baths
    • Built 1999

    Last Sold Summary

    • 1 Day On Market

    Current Estimated Value $299,163

    Last Listing Agent Lori Rogers Keller Williams Realty Centre

    2505 Coach House Way Unit 3D, Frederick, MD 21702
  • 9176 Kenway Ln, Frederick, MD 21704
    9176 Kenway Ln, Frederick, MD 21704
    9176 Kenway Ln, Frederick, MD 21704
    /53

    $630,000 Sold Jun 18, 2025

    9176 Kenway Ln, Frederick, MD 21704

    • 3 Beds
    • 3.5 Baths
    • 2,553 Sq Ft
    • Built 2017

    Last Sold Summary

    • $247/SF
    • 5 Days On Market

    Current Estimated Value $626,193

    Last Listing Agent Bob Lucido Keller Williams Lucido Agency

    9176 Kenway Ln, Frederick, MD 21704
  • 6695 Springhill Dr, Frederick, MD 21702
    6695 Springhill Dr, Frederick, MD 21702
    6695 Springhill Dr, Frederick, MD 21702
    /56

    $660,000 Sold Jul 15, 2025

    6695 Springhill Dr, Frederick, MD 21702

    • 4 Beds
    • 2.5 Baths
    • 3,569 Sq Ft
    • Built 1993

    Last Sold Summary

    • $185/SF
    • 7 Days On Market

    Current Estimated Value $679,267

    Last Listing Agent Lauren Kremers Century 21 Redwood Realty

    6695 Springhill Dr, Frederick, MD 21702
  • 8611 Burnt Hickory Cir, Frederick, MD 21704
    8611 Burnt Hickory Cir, Frederick, MD 21704
    8611 Burnt Hickory Cir, Frederick, MD 21704
    /40

    $660,000 Sold May 13, 2025

    8611 Burnt Hickory Cir, Frederick, MD 21704

    • 4 Beds
    • 4 Baths
    • 2,160 Sq Ft
    • Built 1978

    Last Sold Summary

    • $306/SF
    • 4 Days On Market

    Current Estimated Value $657,022

    Last Listing Agent Ronald Wolfe Charis Realty Group

    8611 Burnt Hickory Cir, Frederick, MD 21704
  • 1031 Staghorn Ave, Frederick, MD 21703
    1031 Staghorn Ave, Frederick, MD 21703
    1031 Staghorn Ave, Frederick, MD 21703
    /29

    $300,000 Sold Apr 16, 2026

    1031 Staghorn Ave, Frederick, MD 21703

    • 2 Beds
    • 1.5 Baths
    • 1,120 Sq Ft
    • Built 1990

    Last Sold Summary

    • $268/SF
    • 2 Days On Market

    Current Estimated Value $297,500

    Last Listing Agent Tony La Scola Welcome Home Realty Group

    1031 Staghorn Ave, Frederick, MD 21703
  • 8294 Waterside Ct, Frederick, MD 21701
    8294 Waterside Ct, Frederick, MD 21701
    8294 Waterside Ct, Frederick, MD 21701
    /41

    $425,000 Sold Jun 18, 2025

    8294 Waterside Ct, Frederick, MD 21701

    • 3 Beds
    • 4 Baths
    • 1,896 Sq Ft
    • Built 1987

    Last Sold Summary

    • $224/SF
    • 7 Days On Market

    Current Estimated Value $419,913

    Last Listing Agent Luke Schlabach Keller Williams Flagship

    8294 Waterside Ct, Frederick, MD 21701
  • 3050 Ivy Meadow Dr, Frederick, MD 21704
    3050 Ivy Meadow Dr, Frederick, MD 21704
    3050 Ivy Meadow Dr, Frederick, MD 21704
    /42

    $915,000 Sold Jul 14, 2025

    3050 Ivy Meadow Dr, Frederick, MD 21704

    • 2 Beds
    • 3 Baths
    • 2,826 Sq Ft
    • Built 2022

    Last Sold Summary

    • $324/SF
    • 87 Days On Market

    Current Estimated Value $894,104

    Last Listing Agent Eric Steinhoff LPT Realty, LLC

    3050 Ivy Meadow Dr, Frederick, MD 21704
  • 4837 Reels Mill Rd, Frederick, MD 21704
    4837 Reels Mill Rd, Frederick, MD 21704
    4837 Reels Mill Rd, Frederick, MD 21704
    /53

    $725,000 Sold May 02, 2025

    4837 Reels Mill Rd, Frederick, MD 21704

    • 4 Beds
    • 3.5 Baths
    • 2,808 Sq Ft
    • Built 1969

    Last Sold Summary

    • $258/SF
    • 0 Days On Market

    Current Estimated Value $732,088

    Last Listing Agent Roberta McNamara RE/MAX Results

    4837 Reels Mill Rd, Frederick, MD 21704
  • 2500 Waterside Dr Unit 110, Frederick, MD 21701
    2500 Waterside Dr Unit 110, Frederick, MD 21701
    2500 Waterside Dr Unit 110, Frederick, MD 21701
    /107

    $342,500 Sold Jul 30, 2025

    2500 Waterside Dr Unit 110, Frederick, MD 21701

    • 2 Beds
    • 2 Baths
    • 1,140 Sq Ft
    • Built 1999

    Last Sold Summary

    • $300/SF
    • 7 Days On Market

    Current Estimated Value $343,799

    Last Listing Agent Julie Byrd Long & Foster Real Estate, Inc.

    2500 Waterside Dr Unit 110, Frederick, MD 21701

Showing Results 121 - 160, Page 4 of 18

Maryland Frederick County Frederick

Recently Sold Real Estate & Homes in Frederick, MD

How to Buy a Home How to Finance a Home How to Sell a Home

Disclaimer: Certain information contained herein is derived from information provided by parties other than Homes.com. All information provided is deemed reliable, but is not guaranteed to be accurate and should be independently verified.

Homes.com Licensing Information

§ 442-H New York Standard Operating Procedures

New York Fair Housing Notice

TREC: Information about brokerage services, Consumer protection notice

California DRE #01937601

Contact Homes.com Brokerage

Copyright © 2026 CoStar Group