HARBOR ISLE
Homes for Sale in Marathon, FL
True comps, carrying-cost math, and listings before the portals.
Market Heat
HARBOR ISLE right now
🟢 Still climbing. The trailing-12-month median ($700K) is up 9.9% from the prior 12 months ($637K) and up 331% since 2012. With about a dozen sales a year, a single closing can swing this number, so read the level and the decade, not one year's move.Momentum Research, record-level floridakeys closed sales, 12-month windows ending July 27. Confidence: Medium (6 and 6 sales in the two windows).
Jump to: Price history & scorecard · Homes for sale · Schools · FAQ
Updated July 27, 2026 · Live data: floridakeys, refreshed twice daily · MLS facts carry their source; interpretation lines are Momentum Research · Data sources & freshness
The 60-Second Overview
HARBOR ISLE market snapshot (as of July 27, 2026): the median sale price is about $700K, and a median 104 days on market for closed sales. The trailing-12-month median is up 10% from the prior 12 months and up 331% since 2012, computed from record-level floridakeys closed sales (6 closings in the current window).
HARBOR ISLE is a community of 105 homes in Marathon, Monroe County, built between 1957 and 2022 (median 1970), with a median living area of about 1,118 square feet. 31% of parcels are homesteaded, the owner-occupancy proxy in the Florida DOR assessment roll (2025 roll, public records).
Price History: What Homes Here Have Actually Sold For
Median sale price over the trailing 12 months ending July 27 of each year, from record-level floridakeys closed sales. Same methodology as every appreciation figure on this page: the 2026 point ($700K) IS the median in the snapshot above, and the move from 2025 ($637K) IS the +9.9% one-year change.
Windows contain 4 to 14 sales each (6 in the current window); every figure carries its sample size, and thin markets swing on single closings. Listing data provided by Florida Keys MLS, Inc. Information is deemed reliable but is not guaranteed by the MLS to be accurate. Deemed reliable but not guaranteed.
The real cost & risk here
Before the list price, the Florida math the portals skip. These are Monroe County typicals — your exact home, flood zone, and insurance quote will vary, so verify each before you offer.
Check it for your address: look up your flood zone (FEMA) · insurance by county · true-cost calculator · Monroe County scorecard.
County typicals from Momentum’s Florida housing data (Zillow & Realtor.com aggregates, Census, FRED), updated monthly; insurance modeled. Flood zone is property-specific — always confirm via FEMA.
The HARBOR ISLE buying strategy.
If we were buying in HARBOR ISLE today, this is the order of operations we would run for our clients.
Underwrite the condition first. Price the roof, HVAC, and systems honestly before judging any list price; condition swings value here more than square footage alone.
Match the home to real comps. Recent sales of similar condition and lot, not the asking price, tell you what a home is worth.
Move deliberately, not desperately. Neither side has a decisive edge, so a well-prepared, fairly-priced offer wins without overpaying.
Line up financing and inspection early. A pre-approval and an inspection plan let you act fast and negotiate from evidence.
Keep an agent in your corner. The listing agent works for the seller; we represent you and prepare a hand-built valuation before any offer in HARBOR ISLE.
A closer look at the HARBOR ISLE market
Homes in HARBOR ISLE trade around a median of $700K, where condition and lot do more to set the final number than the asking price does.
The trailing-12-month median up 10% year over year. Homes that do trade take a median 104 days on market, useful leverage on any listing that has lingered.
The housing stock is 105 homes built between 1957 and 2022, and 31% of parcels are homesteaded — the owner-occupancy proxy in the Florida DOR assessment roll.
The location and the amenities are priced into every listing in HARBOR ISLE. The deal is won or lost on condition, the comps, and the renovation math.
Momentum Buy Score.
Our proprietary 0 to 10 read across the factors that decide how a home in HARBOR ISLE buys, holds, and resells. Momentum Research; not an appraisal.
Momentum Intelligence Scores are our proprietary, qualitative assessment on a 0 to 10 scale, built from the record-level market data on this page. They are a framework for comparing communities, not a guarantee of future value and not advice on a specific home; unlike an automated value estimate they do not price your home, they grade the community on evidence you can inspect. Composite is the plain average of the 4 factors (5.4). Basis: Long-Term Appreciation +331% since 2012; Recent Direction +9.9% year-over-year; Owner Commitment 31% owner-occupied; Pricing Power 85.1% sale-to-list. Refreshed with each data update.
HOA, CDD & Fees
- Mandatory HOA — confirm current dues
- Any club/amenity membership is billed separately
Confirm the current HOA dues, exactly what they cover, and any CDD bond or special assessment for a specific address before you offer.
Tools for a HARBOR ISLE buy.
Free calculators to pressure-test the real cost before you tour.
Selling here is won on condition and pricing to real comps, not an automated estimate. The right number comes from closed HARBOR ISLE sales matched to your home.
Price it to the comps and condition, not an automated estimate.
If you are thinking about selling in HARBOR ISLE, the right list price comes from recent comparable sales matched to your home's condition and location, not an automated estimate.
What is your HARBOR ISLE home worth?
Get a no-obligation home value based on real comparable sales in HARBOR ISLE, not an automated guess. Tell us about your home and we will personally prepare your numbers and a pricing strategy. No obligation, no spam.
See homes for sale in HARBOR ISLE on the map →
Frequently Asked Questions
What is the median home price in HARBOR ISLE?
How long do homes in HARBOR ISLE take to sell?
How many homes are in HARBOR ISLE?
What share of HARBOR ISLE is owner-occupied?
When were the homes in HARBOR ISLE built?
Do cash buyers compete in HARBOR ISLE?
Have HARBOR ISLE home prices gone up?
Who is the best real estate agent for HARBOR ISLE?
How do I find a top Marathon real estate agent who knows HARBOR ISLE?
Can Momentum Realty connect me with an agent for HARBOR ISLE?
Data sources & freshness
| Community market stats | floridakeys closed sales, 12-month windows ending July 27, 2026 |
| Housing stock & ownership | Florida DOR 2025 assessment roll (street-list match (5 streets, ZIP 33050)) |
| Historical depth | Closed-sale records back to 2006 (119 transactions analyzed) |
Verify the primary sources yourself: Florida DOR · U.S. Census · FEMA flood maps · Citizens Property Insurance.
Momentum Research figures are our own analysis of floridakeys records; MLS data is deemed reliable but not guaranteed. Methodology: how Momentum market scores are computed. Market metrics describe homes for sale and recent sales, not residents.
Own a home here?
You just read the data. Now see what your home is worth.
The numbers on this page move markets in the aggregate. The number that matters to you is what a buyer pays for your address. Momentum sells for 1.25% above the floridakeys member average and 8 days faster, and we’ll price yours against live your area comps.
Looking to buy here? Search homes for sale →
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A real valuation with real comps from a local listing agent, not an instant algorithm. Response within one business day.
See how HARBOR ISLE fits the bigger picture — live prices, inventory, and Momentum Scores:
More Marathon & The Florida Keys & Monroe County guides
Compare before you commit - every guide covers pricing, HOA/CDD, insurance posture, and fit. Browse all of The Florida Keys & Monroe County or the full Neighborhood Finder.