All listings
Pending
Pending1 / 40
Photo 1 of 40
Waterfront · Condominium
$3,400,000$1,197 / sqft
430 Grand Bay Dr # 307, Key Biscayne FL 33149
Listed
3
Bedrooms
4
Bathrooms
2,840 sqft
Interior
1999
Year built
$3,118 / mo
HOA
Condominium
Type
About this home
Step off your private elevator into your own foyer and feel instantly at home. This updated, light-filled 3BR + maid's quarters / 4BA offers a wonderfully functional layout - open living and dining area, family room, and a partially open kitchen with snack counter, all flowing to a spacious garden terrace with peaceful green views. Three full ensuite bedrooms. The primary suite is bright and spacious with its own private balcony. Impact windows throughout. Move-in ready. Boutique building. Enjoy Grand Bay's five-star amenities: beach service, pool, fitness center, concierge, valet, tennis and padel courts, and more - all steps from the Ritz-Carlton! Island living at its finest.
Features
- Lobby
- First Floor Entry
- Built-in Features
- Closet Cabinetry
- Cooking Island
- Entrance Foyer
- Roman Tub
- Stacked Bedroom
- Family Room
- Maid/In-Law Quarters
- Utility Room/Laundry
- Open Balcony
Run the numbers
We fill in the price and the building's HOA dues. That leaves tax, insurance and maintenance — they depend on your exemptions, your insurer and the unit, so we don't guess them. Rent starts from what comparable units are asking nearby. Vacancy and the loan terms below start at common defaults; change them.
Median asking rent for 3-bed rentals in Key Biscayne, from 39 active listings; the middle half ask $9,000–$19,000.That is what landlords ask, not what units let for — edit it if you know better.
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 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. We are not a lender and neither offer nor arrange financing. 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.