47

Recently Sold Homes in 53531

Section Image
  • 317 Morningside Dr, Deerfield, WI 53531
    317 Morningside Dr, Deerfield, WI 53531
    317 Morningside Dr, Deerfield, WI 53531
    /25

    $260,000

    Sold Oct 22, 2025

    317 Morningside Dr, Deerfield, WI 53531

    • 2 Beds
    • 2.5 Baths
    • 1,276 Sq Ft
    • Built 2018

    Last Sold Summary

    • 2% Above List Price
    • $204/SF
    • 2 Days On Market

    Current Estimated Value $276,367

    Last Listing Agent Amy Lessing Compass Real Estate Wisconsin

    317 Morningside Dr, Deerfield, WI 53531
  • 174 Savannah Pkwy, Deerfield, WI 53531
    174 Savannah Pkwy, Deerfield, WI 53531
    174 Savannah Pkwy, Deerfield, WI 53531
    /24

    $115,430

    Sold Jan 16, 2026

    174 Savannah Pkwy, Deerfield, WI 53531

    • Land
    • 11,325 Sq Ft
    • $443,962 per Acre

    Last Sold Summary

    • 6% Above List Price
    • 1,000 Days On Market

    Current Estimated Value $115,823

    Last Listing Agent Kristin Lemke Wisconsin Real Estate Prof, LLC

    174 Savannah Pkwy, Deerfield, WI 53531
  • 5010 Ridge Rd, Deerfield, WI 53531
    5010 Ridge Rd, Deerfield, WI 53531
    5010 Ridge Rd, Deerfield, WI 53531
    /69

    $510,000

    Sold Dec 01, 2025

    5010 Ridge Rd, Deerfield, WI 53531

    • 4 Beds
    • 3 Baths
    • 2,626 Sq Ft
    • Built 1900

    Last Sold Summary

    • 15% Below List Price
    • $194/SF
    • 24 Days On Market

    Current Estimated Value $520,620

    Last Listing Agent MHB Real Estate Team MHB Real Estate

    5010 Ridge Rd, Deerfield, WI 53531
  • 3860 Amber Ln, Deerfield, WI 53531
    3860 Amber Ln, Deerfield, WI 53531
    /2

    $658,000

    Sold Jun 02, 2025

    3860 Amber Ln, Deerfield, WI 53531

    • 3 Beds
    • 2.5 Baths
    • 2,610 Sq Ft
    • Built 1979

    Last Sold Summary

    • 5% Above List Price
    • $252/SF
    • 15 Days On Market

    Current Estimated Value $662,581

    Last Listing Agent Mark Voss Latitude Regenerative Real Estate

    3860 Amber Ln, Deerfield, WI 53531
  • 322 Kleine St, Deerfield, WI 53531

    $420,000

    Sold Dec 11, 2025

    322 Kleine St, Deerfield, WI 53531

    • 3 Beds
    • 2 Baths
    • 1,883 Sq Ft

    Last Sold Summary

    • 1% Below List Price
    • $223/SF
    • 10 Days On Market

    Current Estimated Value $417,872

    Last Listing Agent Sherie Nelson Realty One Group Luminous

    322 Kleine St, Deerfield, WI 53531
  • 1545 Burve Rd, Deerfield, WI 53531
    1545 Burve Rd, Deerfield, WI 53531
    1545 Burve Rd, Deerfield, WI 53531
    /73

    $670,000

    Sold Jul 01, 2025

    1545 Burve Rd, Deerfield, WI 53531

    • 3 Beds
    • 3 Baths
    • 2,435 Sq Ft
    • Built 1974

    Last Sold Summary

    • 5% Above List Price
    • $275/SF
    • 6 Days On Market

    Current Estimated Value $645,427

    Last Listing Agent Nina Ristow Turning Point Realty

    1545 Burve Rd, Deerfield, WI 53531
  • 100 Oak Ridge Ct, Deerfield, WI 53531
    100 Oak Ridge Ct, Deerfield, WI 53531
    100 Oak Ridge Ct, Deerfield, WI 53531
    /62

    $435,000

    Sold Dec 05, 2025

    100 Oak Ridge Ct, Deerfield, WI 53531

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

    Last Sold Summary

    • 1% Below List Price
    • $181/SF
    • 71 Days On Market

    Current Estimated Value $428,739

    Last Listing Agent Areal Guenther Realty Executives Cooper Spransy

    100 Oak Ridge Ct, Deerfield, WI 53531
  • 246 Concord Ln, Deerfield, WI 53531
    246 Concord Ln, Deerfield, WI 53531
    246 Concord Ln, Deerfield, WI 53531
    /76

    $401,000

    Sold Mar 02, 2026

    246 Concord Ln, Deerfield, WI 53531

    • 4 Beds
    • 3.5 Baths
    • 2,078 Sq Ft
    • Built 2007

    Last Sold Summary

    • 6% Above List Price
    • $193/SF
    • 4 Days On Market

    Current Estimated Value $397,019

    Last Listing Agent Laura Breunig First Weber Inc

    246 Concord Ln, Deerfield, WI 53531
  • 405 Pheasant Ct, Deerfield, WI 53531
    405 Pheasant Ct, Deerfield, WI 53531
    405 Pheasant Ct, Deerfield, WI 53531
    /42

    $459,000

    Sold May 22, 2025

    405 Pheasant Ct, Deerfield, WI 53531

    • 3 Beds
    • 3.5 Baths
    • 2,772 Sq Ft
    • Built 2005

    Last Sold Summary

    • $166/SF
    • 16 Days On Market

    Current Estimated Value $468,710

    Last Listing Agent Tiffany Tobias Stark Company, REALTORS

    405 Pheasant Ct, Deerfield, WI 53531
  • Lot 2 Center St, Deerfield, WI 53531
    Lot 2 Center St, Deerfield, WI 53531
    Lot 2 Center St, Deerfield, WI 53531
    /5

    $99,900

    Sold Oct 29, 2025

    Lot 2 Center St, Deerfield, WI 53531

    • Land
    • 20,037 Sq Ft
    • $217,174 per Acre

    Last Sold Summary

    • 164 Days On Market

    Last Listing Agent Matt Winzenried Realty Executives Cooper Spransy

    Lot 2 Center St, Deerfield, WI 53531
  • 14 N Prairie St, Deerfield, WI 53531
    14 N Prairie St, Deerfield, WI 53531
    14 N Prairie St, Deerfield, WI 53531
    /39

    $337,500

    Sold Aug 29, 2025

    14 N Prairie St, Deerfield, WI 53531

    • 3 Beds
    • 2 Baths
    • 1,357 Sq Ft

    Last Sold Summary

    • 1% Below List Price
    • $249/SF
    • 14 Days On Market

    Current Estimated Value $335,077

    Last Listing Agent Pete Nissler Century 21 Affiliated

    14 N Prairie St, Deerfield, WI 53531
  • 1778 Strawberry Rd, Deerfield, WI 53531
    1778 Strawberry Rd, Deerfield, WI 53531
    1778 Strawberry Rd, Deerfield, WI 53531
    /56

    $700,000

    Sold Oct 31, 2025

    1778 Strawberry Rd, Deerfield, WI 53531

    • 4 Beds
    • 3 Baths
    • 3,604 Sq Ft
    • Built 2000

    Last Sold Summary

    • 1% Above List Price
    • $194/SF
    • 6 Days On Market

    Current Estimated Value $717,854

    Last Listing Agent Jammie Trapp RE/MAX Preferred

    1778 Strawberry Rd, Deerfield, WI 53531
  • 15 N Western Ave, Deerfield, WI 53531
    15 N Western Ave, Deerfield, WI 53531
    15 N Western Ave, Deerfield, WI 53531
    /33

    $365,000

    Sold Sep 24, 2025

    15 N Western Ave, Deerfield, WI 53531

    • 4 Beds
    • 2 Baths
    • 2,354 Sq Ft
    • Built 1948

    Last Sold Summary

    • 1% Above List Price
    • $155/SF
    • 26 Days On Market

    Current Estimated Value $379,925

    Last Listing Agent Alan Mikkelson EXP Realty, LLC

    15 N Western Ave, Deerfield, WI 53531
  • 316 Washburn Rd, Deerfield, WI 53531
    316 Washburn Rd, Deerfield, WI 53531
    316 Washburn Rd, Deerfield, WI 53531
    /38

    $360,000

    Sold Dec 18, 2025

    316 Washburn Rd, Deerfield, WI 53531

    • 4 Beds
    • 2.5 Baths
    • 2,359 Sq Ft
    • Built 1989

    Last Sold Summary

    • 8% Below List Price
    • $153/SF
    • 31 Days On Market

    Current Estimated Value $369,571

    Last Listing Agent Justin Hurajt Stark Company, REALTORS

    316 Washburn Rd, Deerfield, WI 53531
  • Lot 2 Bue St, Deerfield, WI 53531
    Lot 2 Bue St, Deerfield, WI 53531
    /2

    $39,000

    Sold Dec 23, 2025

    Lot 2 Bue St, Deerfield, WI 53531

    • Land
    • 9,147 Sq Ft
    • $185,714 per Acre

    Last Sold Summary

    • 15% Below List Price
    • 54 Days On Market

    Last Listing Agent Donna LaBarge Badger Realty Team

    Lot 2 Bue St, Deerfield, WI 53531
  • 148 Hidden Valley Trail, Deerfield, WI 53531

    $523,900

    Sold Nov 26, 2025

    148 Hidden Valley Trail, Deerfield, WI 53531

    • 3 Beds
    • 2 Baths
    • 1,640 Sq Ft

    Last Sold Summary

    • 1% Below List Price
    • $319/SF
    • 33 Days On Market

    Last Listing Agent Ryan Prellwitz Loos Custom Homes,LLC

    148 Hidden Valley Trail, Deerfield, WI 53531
  • 201 Hjemdal Ln, Deerfield, WI 53531
    201 Hjemdal Ln, Deerfield, WI 53531
    201 Hjemdal Ln, Deerfield, WI 53531
    /32

    $280,000

    Sold Sep 04, 2025

    201 Hjemdal Ln, Deerfield, WI 53531

    • 3 Beds
    • 2 Baths
    • 1,710 Sq Ft
    • Built 1998

    Last Sold Summary

    • $164/SF
    • 3 Days On Market

    Current Estimated Value $282,834

    Last Listing Agent Jo Ferraro EXP Realty, LLC

    201 Hjemdal Ln, Deerfield, WI 53531
  • 310 Washburn Rd, Deerfield, WI 53531
    310 Washburn Rd, Deerfield, WI 53531
    310 Washburn Rd, Deerfield, WI 53531
    /36

    $375,000

    Sold Jul 31, 2025

    310 Washburn Rd, Deerfield, WI 53531

    • 3 Beds
    • 2 Baths
    • 2,376 Sq Ft
    • Built 1991

    Last Sold Summary

    • $158/SF
    • 4 Days On Market

    Current Estimated Value $387,212

    Last Listing Agent Donna LaBarge Badger Realty Team

    310 Washburn Rd, Deerfield, WI 53531
  • 430 Drumlin Hill, Deerfield, WI 53531
    430 Drumlin Hill, Deerfield, WI 53531
    /2

    $340,000

    Sold Jul 31, 2025

    430 Drumlin Hill, Deerfield, WI 53531

    • 3 Beds
    • 2 Baths
    • 1,380 Sq Ft
    • Built 2005

    Last Sold Summary

    • $246/SF
    • 0 Days On Market

    Current Estimated Value $354,271

    Last Listing Agent . FSBO Comp FSBO Comp

    430 Drumlin Hill, Deerfield, WI 53531
  • 3759 Oak Park Rd, Deerfield, WI 53531
    3759 Oak Park Rd, Deerfield, WI 53531
    3759 Oak Park Rd, Deerfield, WI 53531
    /81

    $740,000

    Sold Dec 18, 2025

    3759 Oak Park Rd, Deerfield, WI 53531

    • 4 Beds
    • 1.5 Baths
    • 2,985 Sq Ft
    • Built 1900

    Last Sold Summary

    • 1% Below List Price
    • $248/SF
    • 68 Days On Market

    Current Estimated Value $726,728

    Last Listing Agent Deena Cortright Restaino & Associates

    3759 Oak Park Rd, Deerfield, WI 53531
  • 3811 Riege Ln, Deerfield, WI 53531
    3811 Riege Ln, Deerfield, WI 53531
    3811 Riege Ln, Deerfield, WI 53531
    /77

    $650,000

    Sold Apr 30, 2026

    3811 Riege Ln, Deerfield, WI 53531

    • 3 Beds
    • 2 Baths
    • 3,220 Sq Ft
    • Built 2013

    Last Sold Summary

    • 7% Below List Price
    • $202/SF
    • 315 Days On Market

    Current Estimated Value $650,969

    Last Listing Agent Tim Vitense Keeps. Real Estate

    3811 Riege Ln, Deerfield, WI 53531
  • 246 Washburn Rd, Deerfield, WI 53531
    246 Washburn Rd, Deerfield, WI 53531
    246 Washburn Rd, Deerfield, WI 53531
    /30

    $250,000

    Sold Jan 09, 2026

    246 Washburn Rd, Deerfield, WI 53531

    • 4 Beds
    • 1.5 Baths
    • 1,735 Sq Ft
    • Built 1975

    Last Sold Summary

    • 3% Below List Price
    • $144/SF
    • 11 Days On Market

    Current Estimated Value $257,619

    Last Listing Agent Leslie Boyea Quorum Enterprises, Inc

    246 Washburn Rd, Deerfield, WI 53531
  • 839 Kimseth Cir, Deerfield, WI 53531
    839 Kimseth Cir, Deerfield, WI 53531
    839 Kimseth Cir, Deerfield, WI 53531
    /41

    $270,000

    Sold Feb 27, 2026

    839 Kimseth Cir, Deerfield, WI 53531

    • 2 Beds
    • 2 Baths
    • 1,155 Sq Ft
    • Built 2000

    Last Sold Summary

    • 2% Above List Price
    • $234/SF
    • 2 Days On Market

    Current Estimated Value $269,392

    Last Listing Agent Erin Swenson Realty Executives Cooper Spransy

    839 Kimseth Cir, Deerfield, WI 53531
  • 4178 Ridge Rd, Deerfield, WI 53531

    $698,470

    Sold Oct 03, 2025

    4178 Ridge Rd, Deerfield, WI 53531

    • 4 Beds
    • 1.5 Baths
    • 2,049 Sq Ft

    Last Sold Summary

    • $341/SF
    • 6 Days On Market

    Current Estimated Value $701,064

    Last Listing Agent Tyler Meyer Shorewest Realtors, Inc.

    4178 Ridge Rd, Deerfield, WI 53531
  • L89 Hidden Valley Trail, Deerfield, WI 53531
    L89 Hidden Valley Trail, Deerfield, WI 53531
    L89 Hidden Valley Trail, Deerfield, WI 53531
    /24

    $86,330

    Sold Feb 19, 2026

    L89 Hidden Valley Trail, Deerfield, WI 53531

    • Land
    • 11,325 Sq Ft
    • $332,038 per Acre

    Last Sold Summary

    • 9% Above List Price
    • 984 Days On Market

    Last Listing Agent Kristin Lemke Wisconsin Real Estate Prof, LLC

    L89 Hidden Valley Trail, Deerfield, WI 53531
  • 180 Savannah Pkwy, Deerfield, WI 53531
    180 Savannah Pkwy, Deerfield, WI 53531
    180 Savannah Pkwy, Deerfield, WI 53531
    /24

    $117,000

    Sold Sep 05, 2025

    180 Savannah Pkwy, Deerfield, WI 53531

    • Land
    • 11,761 Sq Ft
    • $433,333 per Acre

    Last Sold Summary

    • 7% Above List Price
    • 872 Days On Market

    Last Listing Agent Kristin Lemke Wisconsin Real Estate Prof, LLC

    180 Savannah Pkwy, Deerfield, WI 53531
  • 93 Savannah Pkwy, Deerfield, WI 53531

    $527,000

    Sold Dec 19, 2025

    93 Savannah Pkwy, Deerfield, WI 53531

    • 4 Beds
    • 2.5 Baths
    • 2,069 Sq Ft

    Last Sold Summary

    • 4% Below List Price
    • $255/SF
    • 68 Days On Market

    Current Estimated Value $528,317

    Last Listing Agent Ryan Prellwitz Loos Custom Homes,LLC

    93 Savannah Pkwy, Deerfield, WI 53531
  • 1109 Nesheim Rd, Deerfield, WI 53531

    $360,000

    Sold Jun 06, 2025

    1109 Nesheim Rd, Deerfield, WI 53531

    • 3 Beds
    • 1.5 Baths
    • 1,360 Sq Ft

    Last Sold Summary

    • 6% Above List Price
    • $265/SF
    • 2 Days On Market

    Current Estimated Value $357,644

    Last Listing Agent Sarah Keily Shorewest Realtors, Inc.

    1109 Nesheim Rd, Deerfield, WI 53531
  • 511 Sager St, Deerfield, WI 53531
    511 Sager St, Deerfield, WI 53531
    511 Sager St, Deerfield, WI 53531
    /36

    $379,900

    Sold Jan 06, 2026

    511 Sager St, Deerfield, WI 53531

    • 3 Beds
    • 2.5 Baths
    • 1,784 Sq Ft
    • Built 1991

    Last Sold Summary

    • $213/SF
    • 14 Days On Market

    Current Estimated Value $372,450

    Last Listing Agent Max Mulhern Rock Realty

    511 Sager St, Deerfield, WI 53531
  • 4335 Oak Park Rd, Deerfield, WI 53531
    4335 Oak Park Rd, Deerfield, WI 53531
    4335 Oak Park Rd, Deerfield, WI 53531
    /73

    $630,000

    Sold May 23, 2025

    4335 Oak Park Rd, Deerfield, WI 53531

    • 4 Beds
    • 2 Baths
    • 2,725 Sq Ft
    • Built 1975

    Last Sold Summary

    • 1% Above List Price
    • $231/SF
    • 22 Days On Market

    Current Estimated Value $628,140

    Last Listing Agent Breana Berry Coldwell Banker Realty

    4335 Oak Park Rd, Deerfield, WI 53531
  • 303 Venture Ln, Deerfield, WI 53531

    $499,900

    Sold Jun 30, 2025

    303 Venture Ln, Deerfield, WI 53531

    • 3 Beds
    • 2 Baths
    • 1,645 Sq Ft

    Last Sold Summary

    • $304/SF
    • 27 Days On Market

    Current Estimated Value $404,041

    Last Listing Agent Ryan Prellwitz Loos Custom Homes,LLC

    303 Venture Ln, Deerfield, WI 53531
  • 524 Pheasant Trail, Deerfield, WI 53531
    524 Pheasant Trail, Deerfield, WI 53531
    524 Pheasant Trail, Deerfield, WI 53531
    /33

    $510,000

    Sold Jun 30, 2025

    524 Pheasant Trail, Deerfield, WI 53531

    • 5 Beds
    • 3 Baths
    • 2,610 Sq Ft
    • Built 2007

    Last Sold Summary

    • 1% Below List Price
    • $195/SF
    • 15 Days On Market

    Current Estimated Value $519,572

    Last Listing Agent Nicolle Herbsleb First Weber Inc

    524 Pheasant Trail, Deerfield, WI 53531
  • 80 Oak Ridge Trail, Deerfield, WI 53531
    80 Oak Ridge Trail, Deerfield, WI 53531
    80 Oak Ridge Trail, Deerfield, WI 53531
    /42

    $490,000

    Sold Aug 29, 2025

    80 Oak Ridge Trail, Deerfield, WI 53531

    • 3 Beds
    • 2.5 Baths
    • 1,707 Sq Ft
    • Built 2024

    Last Sold Summary

    • 8% Below List Price
    • $287/SF
    • 39 Days On Market

    Current Estimated Value $493,338

    Last Listing Agent The 608 Team EXP Realty, LLC

    80 Oak Ridge Trail, Deerfield, WI 53531
  • 633 Autumn Wood Pkwy, Deerfield, WI 53531
    633 Autumn Wood Pkwy, Deerfield, WI 53531
    633 Autumn Wood Pkwy, Deerfield, WI 53531
    /49

    $408,000

    Sold Nov 07, 2025

    633 Autumn Wood Pkwy, Deerfield, WI 53531

    • 4 Beds
    • 2 Baths
    • 2,271 Sq Ft
    • Built 2003

    Last Sold Summary

    • 4% Below List Price
    • $180/SF
    • 31 Days On Market

    Current Estimated Value $412,218

    Last Listing Agent Matt Kornstedt Stark Company, REALTORS

    633 Autumn Wood Pkwy, Deerfield, WI 53531
  • Lot 1 Bue St, Deerfield, WI 53531
    Lot 1 Bue St, Deerfield, WI 53531
    Lot 1 Bue St, Deerfield, WI 53531
    /3

    $39,000

    Sold Dec 23, 2025

    Lot 1 Bue St, Deerfield, WI 53531

    • Land
    • 9,147 Sq Ft
    • $185,714 per Acre

    Last Sold Summary

    • 15% Below List Price
    • 54 Days On Market

    Last Listing Agent Donna LaBarge Badger Realty Team

    Lot 1 Bue St, Deerfield, WI 53531
  • 207 Holman Rd, Deerfield, WI 53531
    207 Holman Rd, Deerfield, WI 53531
    207 Holman Rd, Deerfield, WI 53531
    /45

    $275,000

    Sold Oct 24, 2025

    207 Holman Rd, Deerfield, WI 53531

    • 3 Beds
    • 2 Baths
    • 1,780 Sq Ft
    • Built 1976

    Last Sold Summary

    • 10% Above List Price
    • $154/SF
    • 3 Days On Market

    Current Estimated Value $288,910

    Last Listing Agent Asher Masino Lauer Realty Group, Inc.

    207 Holman Rd, Deerfield, WI 53531
  • 631 Meadow Trace, Deerfield, WI 53531
    631 Meadow Trace, Deerfield, WI 53531
    631 Meadow Trace, Deerfield, WI 53531
    /59

    $398,500

    Sold Feb 13, 2026

    631 Meadow Trace, Deerfield, WI 53531

    • 3 Beds
    • 4 Baths
    • 1,941 Sq Ft
    • Built 2007

    Last Sold Summary

    • $205/SF
    • 37 Days On Market

    Current Estimated Value $396,236

    Last Listing Agent Roxane Schiller RE/MAX Property Shop

    631 Meadow Trace, Deerfield, WI 53531
  • 22 Sweet Briar Ln, Cambridge, WI 53523
    22 Sweet Briar Ln, Cambridge, WI 53523
    22 Sweet Briar Ln, Cambridge, WI 53523
    /30

    $330,000

    Sold Jul 29, 2025

    22 Sweet Briar Ln, Cambridge, WI 53523

    • 2 Beds
    • 1 Bath
    • 1,200 Sq Ft
    • Built 2005

    Last Sold Summary

    • 2% Above List Price
    • $275/SF
    • 1 Day On Market

    Current Estimated Value $323,480

    Last Listing Agent Donna LaBarge Badger Realty Team

    22 Sweet Briar Ln, Cambridge, WI 53523
  • 9 N Grand Ave, Deerfield, WI 53531
    9 N Grand Ave, Deerfield, WI 53531
    9 N Grand Ave, Deerfield, WI 53531
    /49

    $335,000

    Sold May 18, 2026

    9 N Grand Ave, Deerfield, WI 53531

    • 2 Beds
    • 1.5 Baths
    • 1,394 Sq Ft
    • Built 1940

    Last Sold Summary

    • 4% Below List Price
    • $240/SF
    • 15 Days On Market

    Current Estimated Value $344,470

    Last Listing Agent Cait Berry Real Broker LLC

    9 N Grand Ave, Deerfield, WI 53531
  • 57 Savannah Pkwy, Deerfield, WI 53531

    $524,900

    Sold Oct 27, 2025

    57 Savannah Pkwy, Deerfield, WI 53531

    • 4 Beds
    • 2.5 Baths
    • 2,172 Sq Ft

    Last Sold Summary

    • 2% Below List Price
    • $242/SF
    • 94 Days On Market

    Last Listing Agent Ryan Prellwitz Loos Custom Homes,LLC

    57 Savannah Pkwy, Deerfield, WI 53531

Showing Results 1 - 40, Page 1 of 2

Wisconsin Dane County Deerfield 53531

Recently Sold Real Estate & Homes in 53531

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