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© 2026 DockOnly™. All rights reserved.

DockOnly™ and Dock Score™ are trademarks of Blue Mar Real Estate Group Inc.

Blue Mar Real Estate Group Inc., Licensed Florida Real Estate Broker

Blue Mar Real Estate Group Inc.

Licensed Florida Real Estate Broker · DBPR License CQ1018554

4000 Ponce De Leon Blvd, Suite 470, Coral Gables, FL 33146

[email protected]

Listing data is provided by participating Multiple Listing Services and is deemed reliable but not guaranteed. Each listing's MLS source and its required disclosures appear with that listing. Dock Score™ is a DockOnly.com rating and is not provided by or affiliated with any MLS or listing broker. NOAA chart data is public domain and for reference only, not for navigation. Full MLS Compliance

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+20

330-340 4th Street

Key Colony, FL, 33051

Active

$1,849,000

330-340 4th Street

Key Colony, FL, 33051

Active

$1,849,000

3

Bedrooms

4

Bathrooms

2,540 sqft

Living Area

1971

Year Built

$1,849,000Tour the dockSchedule a Showing
Navigation note: Navigation routes show the shortest mapped path to open water. A vessel taller than the binding bridge clearance may still reach open water via a longer alternate route that we don't currently map. Verify navigability with a local captain or surveyor before relying on it.

6,600

Lot Size (sqft)

107

Days on Market

Dock Score™

DockOnly
87
Excellent

What shaped this score

✓Canal
✓Dock with boat lift
✓Bridge-free to bay & ocean
✓Fits boats up to ~55ft (est.)

DockOnly.com rating, not provided by the MLS or listing broker.

Dock & Water AccessMLS

Canal Front📝 deep water

AI Aerial Imagery Detection

Dock DetectedBoat Lift DetectedSeawall Detected~47-63 ft dock

Detected by AI from open-source aerial mapping imagery and may not reflect current conditions. This information was not provided by the MLS or listing broker. Always verify dock infrastructure with the listing agent.

Navigation RouteDockOnly

Data sources: SFWMD AHED waterway polygons · FHWA National Bridge Inventory 2024 · Not provided by the MLS or listing broker.

Description

WATERFRONT BEAUTIFULLY RENOVATED DUPLEX 330-340, 2BR 2BA Upper Level, 1BR 1.5BA Lower Level, both with Full Kitchens, in Key Colony Beach, a NO HOA Municipality, on Marathon Island MM53. New 15K lbs. Boat Lift 2022, 60 Ft Deep Water Dock, Extra Wide Canal, Multiple Electrical Outlets, 3 Fresh Water Spigots. House is equipped with Surge Protection, and a Transfer Switch for a portable generator. Exterior Motion Lights equipped with Security Cameras. EXCELLENT RENTAL INCOME OPPORTUNITY, 7 Day Rentals allowed. Rent the Upper and Lower units to separate parties at the same time, and or live in one and rent the other unit. Beautiful New Pool Heated-Chilled 2022, with a Saltwater system that uses a salt generator, offering lower maintenance, softer water, and reduced skin-eye irritation. New Pool-Cool Deck concrete patio in 2022, that reduces surface temperatures. Outdoor Shower. Metal Roof 2013. Hurricane Accordion and Metal Bahama Shutters in 2021. Upgraded Electrical system in 2022. Upgraded Flooring, Doors, and Windows. Mini-Split AC unit 2021. Upper Level Covered Balcony, beautiful views of the new Sparkling Pool and Boat Dock-Canal. Ample Storage, 3 large outdoor access rooms, and a shed. Excellent Parking 12 Cars, 2 RVs, and 2 Boats/Trailers storage. Ocean side, minutes to World Class Fishing-Diving in the Gulfstream, Coffins Patch Reef, and Sombrero Reef Lighthouse. Easy Bayside access via Vaca Cut in minutes. Join the Cabana Club, steps away, for beach access and excellent dining. Key Colony Beach amenities includes a Golf Course 9 Hole Par 3, Tennis and Pickle Ball Courts, Basketball, Bocce Ball, Corn Hole, Horseshoes. Enjoy the Parks, Playgrounds, Walking and Bike pathways. Key Colony Beach, Paradise Awaits!

Schedule a Showing

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Location

Key Colony, FL, 33051

No price history available for this property.

Displayed by Blue Mar Real Estate Group Inc., Licensed Florida Real Estate Broker (DBPR CQ1018554) · [email protected]

Listing courtesy of Water Vista Realty, Inc. via Florida Keys MLS

Last updated: 4/20/2026

© 2026 Florida Keys Board of REALTORS®, Inc. All rights reserved. The data relating to real estate for sale on this website comes in part from the Internet Data Exchange (IDX) program of the Florida Keys Board of REALTORS®. Information is deemed reliable but not guaranteed and should be independently verified. All properties are subject to prior sale, change, or withdrawal.

IDX information is provided exclusively for consumers' personal, non-commercial use. It may not be used for any purpose other than to identify prospective properties consumers may be interested in purchasing.

Dock Score™

DockOnly
87
Excellent

What shaped this score

✓Canal
✓Dock with boat lift
✓Bridge-free to bay & ocean
✓Fits boats up to ~55ft (est.)

DockOnly.com rating, not provided by the MLS or listing broker.

Nearest Bridge Clearances

Florida Keys, critical for tall/large vessels

No bridge data available for this location.
FEMA Flood Zone AE
BFE: 6ft

Special Flood Hazard Area

View FEMA Flood Map →
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Mortgage Calculator

Estimate your monthly payment for this waterfront property

20%

$369,800 down

%
Principal & Interest$9,594/mo
Property Tax (est. ~1.2%, varies by county)$1,849/mo
Home Insurance (est.)$250/mo
Total Monthly Payment$11,693
Loan Amount: $1,479,200Rate: 6.75%
Get Pre-Qualified

Estimated payments only. Actual rates and terms may vary.

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