Single Family Residence
520 S Mashta Dr
520 S Mashta Dr, Key Biscayne FL 33149
$19,900,000
5 Beds · 4 Baths · 3,085 SqFt
See estimated monthly costThis listing is courtesy of Coldwell Banker Realty. Maureen Jauregui
Overview
Seize a rare opportunity to create a landmark waterfront estate on one of the largest residential lots in Key Biscayne’s exclusive Mashta Island enclave. Spanning an extraordinary 22,140 square feet, this exceptional property offers 138 feet of pristine water frontage and sweeping open water views, providing an unparalleled setting for a world class residence. Plans by renowned architect, Pablo Corazzini of Vitalini Corazzini Architects, are available to the buyer, offering a thoughtfully conceived vision that takes full advantage of the property’s remarkable scale, premier waterfront setting, and spectacular sunsets. The proposed design creates an extraordinary canvas for sophisticated indoor-outdoor living and entertaining, should the buyer choose to pursue the concept. With its exceptional lot size, expansive water frontage, and coveted Mashta Island address, this is a truly irreplaceable opportunity to create a legacy estate in one of South Florida’s most prestigious waterfront communities.
Facts & features
Interior
- Living area (sq ft)
- 3,085
- Full bathrooms
- 4
- First Floor Entry
- Split Bedroom
- Family Room
Building & exterior
- Year built
- 1961
- Lot size (sq ft)
- 22,140
- Garage spaces
- 2
- Covered spaces
- 2
- Waterfront
- Yes
- Bay
- Direct Ocean
- Ocean Access
- Seawall
- Driveway
HOA (homeowners association)
- Ok To Lease
Taxes
- Annual tax
- $201,741
- Tax year
- 2026
- Parcel number
- 24-52-05-009-0170
Assigned schools
- Elementary
- Keybiscayne
- Middle
- Ponce De Leon
- High
- Coral Gables
Listing
- MLS number
- A12071221
- Property type
- Single Family Residence
- Price per SqFt
- $6,451
- Subdivision
- MASHTA ISLAND A REPLAT OF
- On market since
- Aug 12, 2026
- Days on market
- 5
Estimated monthly cost
$132,362 per month
- Principal & interest (30 yr)
- $100,625
- Property tax
- $16,812
- Insurance (estimated)
- $14,925
An estimate for comparison only — not a loan offer, a quote, or a commitment to lend. Actual taxes, insurance and financing terms will differ.
Location
Nearby schools
- Key Biscayne K-8 Center
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