Duplex with Unfinished Third
New
For Sale
$1,400,000
646 William Street, Key West, FL 33040
Residential, Key West, FL
Property Size1,780 SF
Lot Size0.09 Acres
Price / SF$786.52
Days on Market5
Property Features for 646 William Street
General Information
Property type
Residential Multi Family
Property subtype
Duplex
Zoning
HHDR - Historic High Dens
Bedrooms
3
Bathrooms
2
Full bathrooms
2
Rooms
Bathroom 1, Bedroom 3, Bathroom 2, Bedroom 2, Bedroom 1
Parking features
Off Street
Security features
Security
Patio and Porch features
Porch
Subdivision
Old Town - Unlisted (1.0)
View
Water
Standard status
Active
APN
00018810000000
Size
1,780 SF
Lot size
0.09 Acres
Taxes and HOA fees
Tax Year
2025
Tax Description
Kw Pt Of Tr 5 C3-569
Tax Annual Amount
13850
Legal Description
Kw Pt Of Tr 5 C3-569
Utilities
Heating system
Hot Water(Heating)
Cooling system
Wall/Window Unit(s), Window Unit(s)
Building Details
Year built
1928
Flooring type
Combo
Building materials
Frame
Roof type
Metal
Architectural style
Other
Listing Agency:
Coldwell Banker Schmitt Real Estate Co. (KW)
(305) 296-7727
Listed By:
Louis M Paez · License #3029661
(305) 395-1081
Added: Sep 23
Changed: Sep 26
Last Checked: Sep 27 at 12:06PM
MLS# 621406
Copyright © 2026 Key West Association of Realtors. All rights reserved. All information provided by the listing agent/broker is deemed reliable but is not guaranteed and should be independently verified.
Investment Insights
Based on property information with market context.
Built in 1928, this 1,780-square-foot, two-and-a-half-story frame residence is configured as a duplex and requires renovation. Finished living space includes four bedrooms and three bathrooms: the first floor has two bedrooms and two bathrooms, and the second floor has two bedrooms and one bathroom. A stairwell leads to an unfinished third floor that is not currently configured as living space.
The property occupies 0.09 acres and is zoned HHDR - Historic High Dens. Exterior features include a metal roof and porch. Heating is hot water, cooling is provided by wall/window units, and off-street parking is listed.
The property occupies 0.09 acres and is zoned HHDR - Historic High Dens. Exterior features include a metal roof and porch. Heating is hot water, cooling is provided by wall/window units, and off-street parking is listed.
Key Highlights
- Two‑and‑a‑half‑story duplex with 1,780 square feet
- Four finished bedrooms and three bathrooms
- Unfinished third floor is not configured as living space
Property Analytics
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Current Use
Lease Details
2
Residential units
Location Intelligence
Trade Area within ½ mile
3,824
Businesses Nearby
Explore this area
Business Placement
Demographics for 33040, FL
35,958
Population
19,001
Households
1.9
Avg Household Size
44
Median Age
38%
College-Educated
92%
High-School Grad
17.7 sq mi
ZIP Area
2,032
Density / Sq Mi
$79,038
Median Household Income
$42,458
Median Earnings
$2,079
Median Rent
$766,400
Median Home Value
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Market
Vacancy Rate% for Multifamily in South region
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Frequently Asked Questions
What type of property is this?
Duplex - The first level has two bedrooms and two bathrooms, while the second floor contains a separate two-bedroom, one-bathroom layout.
Where is this duplex located?
The property is located at 646 William Street Key West, FL.
What is the asking price?
The asking price for this property is $1,400,000.
What are key features of this property?
This property features: Two‑and‑a‑half‑story duplex with 1,780 square feet; Four finished bedrooms and three bathrooms; Unfinished third floor is not configured as living space
