Harbor Isle
Homes for Sale in Marathon, FL
All 178 homes for sale in Marathon, FL · median $1,225,000 · 183 homes for sale in 33050 · Monroe County homes for sale
True comps, carrying-cost math, and listings before the portals.
Market Heat
Over the 12 months ending 2026-09-20, 6 recorded sales closed at a median of $627,500, a median 94 days on market, sellers accepting 85% of original asking (-13% versus the prior year). At the median price and Monroe County's FY2025-26 rate of 8.816 mills, annual property tax runs about $5,530 ($5,180 with the full homestead exemption).
| Location | Marathon, Monroe County, FL · ZIP 33050 |
|---|---|
| Homes in the community | 105 (FL DOR 2025 assessment roll) |
| Years built | 1957–2022 (median 1970) |
| Typical living area | 1,118 sq ft (median) |
| Sale prices, last 12 months | $627,500 median across 6 closed sales · -12.8% vs the prior 12 months |
| Days on market (closed sales) | 94 median |
| Owner-occupied (homestead) share | 31% |
Data as of September 20, 2026. Listing data provided by Florida Keys MLS, Inc. Information is deemed reliable but is not guaranteed by the MLS to be accurate; housing-stock figures from Florida Department of Revenue public records. Market figures describe homes, not residents. Cite as: Momentum Realty, “HARBOR ISLE key facts,” movewithmomentum.com/neighborhoods/harbor-isle, data as of September 20, 2026.
Harbor Isle right now
🔴 Off the recent peak. The trailing-12-month median ($628K) is down 12.8% from the prior 12 months ($720K) and up 337% 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 Florida Keys MLS closed sales, 12-month windows ending September 20. Confidence: Low (6 and 5 sales in the two windows).
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· Updated September 21, 2026 · Live data: Florida Keys MLS, refreshed twice daily · MLS facts carry their source; interpretation lines are Momentum Research · Data sources & freshness
Nearby homes for sale
No active listings inside HARBOR ISLE right now. These are the 6 closest homes on the market, by straight-line distance from the community's center; some may sit just outside its boundary.
Listing data from the MLS feeds named on each listing page; deemed reliable but not guaranteed. Refreshed nightly.
The 60-Second Overview
Harbor Isle market snapshot (as of September 20, 2026): the median sale price is about $628K, and a median 95 days on market for closed sales. The trailing-12-month median is down 13% from the prior 12 months and up 337% since 2012, computed from record-level Florida Keys MLS closed sales (6 closings in the current window).
In ZIP 33050 (Marathon), 209 homes closed in the last 12 months at a median of $799K, up 6.4% year over year, with a median 87 days on market. See the live ZIP 33050 housing market and the Monroe County market.
County records show 7 qualified sales in HARBOR ISLE across 2024–2025 (4 in 2024, 3 in 2025), median $675,000 — the last recorded sale per parcel on the Florida DOR 2025 assessment roll, independent of the MLS.
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 September 20 of each year, from record-level Florida Keys MLS closed sales. Same methodology as every appreciation figure on this page: the 2026 point ($628K) IS the median in the snapshot above, and the move from 2025 ($720K) IS the -12.8% one-year change.
Windows contain 4 to 15 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.
14% of homes for sale in ZIP 33050 are already under contract (under contract ÷ under contract + active listings) — a read on how much of the available inventory buyers have already claimed. Source: MLS data (2026-09-20).
Housing distress & ownership in HARBOR ISLE, Marathon
Who owns here, how much is not owner-occupied, and how much for-sale inventory is under distress.
Source: Momentum Realty Research. Ownership & parcels from the FL DOR 2025 tax roll; distress from MLS active-listing status/remarks; price from MLS closed sales. 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 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 $628K, where condition and lot do more to set the final number than the asking price does.
The trailing-12-month median down 13% year over year. Homes that do trade take a median 95 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 (4.0). Basis: Long-Term Appreciation +337% since 2012; Recent Direction -12.8% year-over-year; Owner Commitment 31% owner-occupied; Pricing Power 85.1% sale-to-list. Refreshed with each data update.
HOA, CDD & Fees
- HOA status not on record. Verify any dues before you offer
- 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 all homes for sale in Marathon →
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?
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?
Where is Harbor Isle, and what county is it in?
Is Harbor Isle a good place to live?
Data sources & freshness
| Community market stats | Florida Keys MLS closed sales, 12-month windows ending September 20, 2026 |
| Housing stock & ownership | Florida DOR assessment roll (street-list match (5 streets, ZIP 33050)) |
| Under-contract shares | Florida Keys MLS records, as of 2026-09-20 |
| Historical depth | Closed-sale records back to 2006 (120 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 Florida Keys MLS 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 Florida Keys MLS member average and 8 days faster, and we’ll price yours against live local 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:
Nearby Communities
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