David Costello

Portland ME

Keller Williams Realty

51 Closed Sales

$50.8M Total Value

$71.6K - $7.5M Price Range

$996.1K Average Price

Prior 5 years

About David

Dave Costello owner and managing partner of RockWater Group, KW Commercial Realty, has been a business leader in the Greater Portland community for more than 30 years. He previously owned and operated Sun Media Group, whose holdings included companies from Southern, Central, and Western Maine. Within the industry, his roles included buying, selling, managing, and developing businesses. In commercial real estate, he worked with Daigle Commercial Group, specializing in the hospitality industry. Dave has extensive experience in management, technology, marketing, and customer service. He brings excellent negotiation skills, a broad knowledge of the local business market, and a passion for helping people facilitate business goals. RockWater Group provides a complete range of commercial real estate services to its clients.

Home Types: House, MultiFamily, Condo, Townhouse, Commercial, Lot/Land

Years of Experience: 7

Education: Rochester Institute of Technology, Bachelor of Science Husson University, Masters of Science

Transaction History

1 Year
2 Year
5 Year

Seller Deals

Total Deals

Total Value

$11,335,000

Average Sale Price

$1,133,500

Price Range

$350K - $5.5M

Buyer Deals

Total Deals

Neighborhoods David is Experienced In

David's Active Listings

$549,000
- 3 Beds
- 2 Baths
- 2,438 Sq Ft
557 Coles Hill Rd

Wells, ME
Set overlooking Merriland Farm Golf Course and just minutes from I-95, Route One, and Wells' beaches, this former berry farm and café offers a rare blend of character, flexibility, and future potential. Originally built as a farmhouse and later converted into a successful café, the property is currently configured and equipped for restaurant use, while also offering possible residential or

David Costello Keller Williams Realty

Recently Sold

$1,050,000 Sold Jan 6, 2026
- 2 Beds
- 3 Baths
- 1,850 Sq Ft
21 Marigold Ln

Falmouth, ME
- 6% Above List
- $568/SF
- 0 Days On Market
- Current Est. Value $1M
David Costello Keller Williams Realty

$610,000 Sold Oct 22, 2025
- 4 Beds
- 2 Baths
- 1,929 Sq Ft
67 Carter St

Portland, ME
- 6% Below List
- $316/SF
- 14 Days On Market
- Current Est. Value $602K
David Costello Keller Williams Realty

$965,000 Sold Aug 26, 2025
- 3 Beds
- 2.5 Baths
- 2,287 Sq Ft
132 Mineral Spring Rd

Unit 1

Windham, ME
- 1% Below List
- $422/SF
- 35 Days On Market
David Costello Keller Williams Realty

$460,000 Sold Aug 19, 2025
- 3 Beds
- 2 Baths
- 1,386 Sq Ft
69 Webb Rd

Windham, ME
- 7% Below List
- $332/SF
- 10 Days On Market
- Current Est. Value $454K
David Costello Keller Williams Realty

$1,050,000 Sold Sep 23, 2024
- 2 Beds
- 2.5 Baths
- 1,705 Sq Ft
308 Chandlers Wharf

Portland, ME
- 19% Below List
- $616/SF
- 197 Days On Market
- Current Est. Value $1M
David Costello Keller Williams Realty

$1,400,000 Sold Aug 19, 2024
- 4 Beds
- 2.5 Baths
- 4,271 Sq Ft
10 Stockholm Dr

Cumberland Center, ME
- 6% Below List
- $328/SF
- 4 Days On Market
David Costello Keller Williams Realty

$306,000 Sold Jun 26, 2024
- 2 Beds
- 1 Bath
- 1,799 Sq Ft
2 Wicklow Place

Lewiston, ME
- 4% Above List
- $170/SF
- 4 Days On Market
- Current Est. Value $320K
David Costello Keller Williams Realty

$550,000 Sold Apr 2, 2024
- 5 Baths
- 6,616 Sq Ft
228 Webster St

Lewiston, ME
- 4% Below List
- $83/SF
- 74 Days On Market
David Costello Keller Williams Realty

$178,500 Sold Apr 1, 2024
- 2 Beds
- 1 Bath
- 1,117 Sq Ft
15 Weybossett St

Lewiston, ME
- $160/SF
- 9 Days On Market
- Current Est. Value $217K
David Costello Keller Williams Realty

David Costello

(207) 531-5464

Homes for Sale by City

David Costello

About David

Transaction History

Seller Deals

Buyer Deals

Production Over Time

1 Year View by Quarter

Seller Deals

Buyer Deals

Seller Deals

Buyer Deals

Production Over Time

5 Year View

Neighborhoods David is Experienced In

David's Listings and Deals

David's Active Listings

Recently Sold