445 Grand Bay Drive

Key Biscayne, FL 33149

$18,900,000

$2,241/ft²

5Beds

5.5Baths

8,435Sq ft

1997Year built

CondoType

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

Waterfront
55+ community

Property details

Listing

MLS #: A11954185
Status: For sale
Listed on: Feb 14, 2026
Days on market: 177 days
Listing data updated: May 4, 2026

Interior

Beds: 5
Baths: 5.5
Living area: 8,435 ft²
Price per ft²: $2,241/ft²
Unit: PH-1A

Building & community

Type: Condo
Year built: 1997
County: Miami-Dade

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): $95,569
Property taxes (est.): $17,325
Home insurance (est.): $600
Flood insurance (est.): —

Estimated total$113,494*/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?