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Condominium at 445 Grand Bay Drive # 1A, Key Biscayne FL 33149Active
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Waterfront · Condominium
$18,900,000$2,241 / sqft

445 Grand Bay Drive # 1A, Key Biscayne FL 33149

5
Bedrooms
6
Bathrooms
8,435 sqft
Interior
1997
Year built
None
HOA
Condominium
Type

About this home

High above the turquoise waters of Key Biscayne rises a penthouse that simply cannot be replicated. Once featured in Architectural Digest, this legendary corner residence at Grand Bay is a statement of scale, design, and presence. From sunrise over the Atlantic to glittering sunsets across Biscayne Bay and the Miami skyline, the views are cinematic in every direction, offering endless blue water, golden light, and exceptional privacy. Spanning an extraordinary 8,435 square feet under air and 2,825 square feet of terraces, totaling 11,260 square feet as per the developer’s floor plan, the residence is defined by soaring 12-foot ceilings and grand proportions throughout. A dramatic foyer leads to a spectacular Grand Room designed for both intimate living and large-scale entertaining. The formal dining room is separate and elegant, while the completely remodeled kitchen and family room provide comfort and functionality. The fully renovated private library and custom bar enhance the home’s entertaining appeal. The primary suite is serene and expansive. All the bathrooms have just been completely remodeled, offering a fresh spa-inspired experience finished to today’s highest standards. Four (4) additional en-suite bedrooms ensure comfort and privacy. The terraces offer expansive outdoor living in the sky, perfect for sunrise mornings and sunset evenings overlooking the water and skyline. This is not simply a penthouse. It is a landmark residence, rare and impossible to duplicate.

Features

  • Built-in Features
  • Closet Cabinetry
  • Entrance Foyer
  • Pantry
  • Volume Ceilings
  • Walk-In Closet(s)
  • Wet Bar
  • Den/Library/Office
  • Family Room
  • Great Room
  • Open Balcony
  • Bay
  • Ocean View
  • Direct Ocean

Location

Approximate — shows the building, not the unit. Open in maps (opens in a new tab)

Estimated loan & HOA

$95,569

Loan payment and HOA only. Property tax and insurance are significant here and are not included.

Principal & interest
$95,569
HOA
None

Illustration only — not a loan offer, quote, or commitment. Assumes a 30-year loan at 6.5% with 20% down (rates as of July 2026); your actual terms will differ.

Schedule a tour

Request a private or video tour with a local agent.

Courtesy of
One Sotheby's International Realty

Run the numbers

We fill in the price and the building's HOA dues. That leaves rent, tax, insurance and maintenance — they depend on your exemptions, your insurer and the unit, so we don't guess them. Vacancy and the loan terms below start at common defaults; change them.

Our default, not a market figure
From the listing
Depends on assessed value & exemptions
Varies widely by building
Repairs, turnover, management

Cap rate
Cash-on-cash
Monthly cash flow
Net operating income

Enter rent, property tax, insurance, maintenance to see the returns. A cap rate calculated without every cost overstates the deal — often by half — so we don't show a partial one.

Illustration only — not a loan offer, quote, or investment advice. The loan fields start at 20% down over 30 years at 6.5% (rates as of July 2026); that is a nominal rate for illustration, not an APR, and your actual terms will differ. Cap rate is unlevered; cash-on-cash counts the down payment as invested capital and excludes closing costs.

Listing data from the MIAMI Association of REALTORS® (MIAMIRE) IDX program. Information deemed reliable but not guaranteed. Demo data shown for layout purposes.