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For sale
  • $1,400,000

    646 William St, Key West, FL 33040

    3beds
    1,780sqft
    : 
    $8,833/mo
    Get pre-qualified
    Duplex
    Built in 1928
    -- sqft lot
    $-- Zestimate®
    $787/sqft
    $-- HOA

    What's special

    Two-and-a-half-story homeThree bathroomsFour bedrooms
    644 William Street The property being sold is 644 William Street. The current property record/card reflects both 644 and 646 William Street, although the property being conveyed is 644 William Street. The structure at 644 William Street is a two-and-a-half-story home currently configured as a duplex and is in need of renovation. The first floor consists of two bedrooms and two bathrooms. The second floor contains two bedrooms and one bathroom. A stairwell provides access to the third floor, which is currently unfinished and is not completed or configured as living space. In its current condition, the property contains four bedrooms and three bathrooms of finished living area, with additional unfinished space on the third floor. The property is currently being used/configured as a duplex and will require renovation.
    13 days
    1,087
    50

    Zillow last checked:

    Listing updated:

    Listed by:

    Louis M Paez 305-395-1081,

    Coldwell Banker Schmitt Real Estate Co. (KW)

    Source: FLKMLS,MLS#: 621406MLS Logo

      Facts & features

      Interior

      Bedrooms & bathrooms
      • Bedrooms: 3
      • Bathrooms: 2
      • Full bathrooms: 2
      Heating
      • Has Heating (Unspecified Type)
      Cooling
      • Wall/Window Unit(s)
      Features
      • Flooring: Combination
      Interior area
      • Total structure area: 1,780
      • Total interior livable area: 1,780 sqft

      Property

      Features
      • Patio & porch: Open Porch/Balcony
      Lot
      • Size: 3,920 Square Feet
      • Dimensions: 65 X 78
      Details
      • Parcel number: 00018810000000
      • Zoning: HHDR - Historic High Density Residential

      Construction

      Type & style
      • Home type: MultiFamily
      • Architectural style: Conch
      • Property subtype: Duplex
      Materials
      • Frame
      Condition
      • Fixer
      • New construction: No
      • Year built: 1928

      Community & HOA

      Community
      • Security: No Security
      • Subdivision: Old Town - Unlisted (1.0)
      HOA
      • Has HOA: No
      • Services included: None
      Location
      • Region: Key West

      Financial & listing details

      • Price per square foot: $787/sqft
      • Tax assessed value: $1,567,206
      • Annual tax amount: $13,849
      • Date on market: 9/25/2026
      • Listing terms: Cash,Conventional

        Estimated market value

        Not available

        Estimated sales range

        Not available

        Not available

        Price history

        DateEventPrice
        9/25/2026Listed for sale$1,400,000$787/sqft
        Source: FLKMLS #621406 Report a problem

        Public tax history

        YearProperty taxesTax assessment
        2025$13,850 +12.9%$1,321,266 +21%
        2023$12,267 +16.4%$1,091,955 +10%
        2022$10,540 +9.6%$992,686 +10%
        2021$9,614 +5%$902,442 +5.5%
        2020$9,156 $855,275 +1%
        2019$9,156 +0.2%$847,153 -7%
        2018$9,141 +0.3%$911,324 -0.2%
        2017$9,109 +3.2%$912,984 +23.8%
        2016$8,829 +7.5%$737,413 +3.5%
        2015$8,215 $712,140
        Find assessor info on the county website

        Monthly payment

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        Payment breakdown

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        HOA fees may include property taxes on listings classified as Co-Ops. Contact the listing agent and/or owner for fee details.
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        Climate risks

        Neighborhood: Old Town

        Getting around

        93 / 100
        Walker's Paradise
        28 / 100
        Some Transit
        97 / 100
        Biker's Paradise

        Nearby schools

        GreatSchools rating

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