6403 Gulf Of Mexico Blvd

Marathon, FL 33050

$995,000

$523/ft²

3Beds

2Baths

1,902Sq ft

1983Year built

CondoType

About this home

Welcome to your Marathon lifestyle package, a fully remodeled 3-bedroom, 2-bath Penthouse offering 1,902 SQFT of luxury coastal living. Rare opportunity includes a 24' boat with marina access w/lifts permitted, combining a move-in-ready residence w/boating lifestyle buyers dream of in the Florida Keys. Designed for comfort and entertaining, this top-floor residence features Versace & marble tile finishes, quartz countertops, New Kitchen & Stainless Steel appliances, New impact windows, 9-ft ceilings, wet bar, private parking, open-concept layout, and wraparound balcony, perfect for tropical breezes, morning coffee, and sunset cocktails. Spacious Primary suite offers balcony access, dual closets & spa-inspired bath w/soaking tub, glass-enclosed shower, makeup station & designer finishes. Enjoy direct marina access & your included 24' boat for fishing, cruising, island hopping & waterfront dining in the Keys. Amenities include covered warehouse storage for your water toys, Lagoon-style pool, jacuzzi, tennis & basketball courts, fitness center, and gated tropical grounds. All located in the heart of Marathon, minutes from Sombrero Beach, Coco Plum Beach, Marathon Airport, Turtle Hospital, Old Seven Mile Bridge & Best waterfront restaurants! World-class boating, fishing, snorkeling & breathtaking sunsets are right outside your door. More than just a Penthouse, this is your private escape, boating base, weekend retreat, future vacation home, and private piece of paradise!

Features

Waterfront

Property details

Listing

MLS #: A12033219
Status: For sale
Listed on: Jun 8, 2026
Days on market: 63 days
Listing data updated: Jun 30, 2026

Interior

Beds: 3
Baths: 2
Living area: 1,902 ft²
Price per ft²: $523/ft²
Unit: 403

Building & community

Type: Condo
Year built: 1983
HOA fee: $1,993/mo
County: Monroe

Lot & exterior

Waterfront: Yes

Days on market, price per ft² and the monthly HOA amount are calculated by this site from the MLS data shown; the association fee is normalized to a monthly figure.

True monthly cost

Mortgage (principal & interest): $5,031
Property taxes (est.): $913
Home insurance (est.): $600
Flood insurance (est.): —
HOA fee: $1,993

Estimated total$8,537*/mo

* Some cost lines aren't available yet for this listing; the total shown is incomplete.

Based on 20% down, a 6.5% rate and a 30-year loan, plus this home's estimated Florida carrying costs. All figures are illustrative estimates — not quotes, not financial or insurance advice.

Sources: flood zone — FEMA National Flood Hazard Layer; mortgage, taxes and insurance figures — this site's own estimates; HOA / CDD — as reported for this listing.

What will this home really cost you?

Building structural health (SIRS)

No filing record found

We couldn't find a SIRS filing record for this building in Florida's public DBPR database. That is not a red flag by itself: buildings under three stories are exempt, recent or mailed-in filings may not appear yet, and the name or address on file may differ from this listing.

Questions about this

What is a SIRS and why does it matter?

Since the Surfside collapse, Florida requires condo and co-op buildings three stories or taller to complete a Structural Integrity Reserve Study: an inspection-based plan that forces the association to fund structural repairs (roof, load-bearing walls, plumbing, electrical) instead of deferring them. It matters because underfunded buildings are the ones that surprise owners with large special assessments.

Has this building filed its SIRS?

We didn't find a filing record for this building in the DBPR's public database. Absence of a record does not mean the building is out of compliance — it may be exempt (under three stories), the filing may be recent or on paper, or the recorded name/address may differ. It IS the right question to ask before offering.

What is a special assessment?

A one-off charge the association levies on every owner when reserves don't cover a needed repair — in older coastal buildings they have ranged from a few thousand to over $100,000 per unit. The SIRS exists precisely to make these predictable and funded in advance. Always review the building's budget, reserves and meeting minutes before buying.

What should I check before buying in this building?

Florida law gives buyers the right to review the association's SIRS, milestone inspection reports, budget and reserves — the full study is available from the association by written request. Nilyan requests and walks through these documents with her buyers as part of the offer process.

Source: Florida DBPR public SIRS reporting database. Filing status is self-reported by the association; this is not an audit, inspection or safety certification, and absence of a record does not mean non-compliance. Data as of July 30, 2026.

Want the full structural picture of this building before you offer?