690 Warren Ln, Key Biscayne FL 33149
About this home
A truly exceptional Miami Modern Tropical residence set on a prime 8,010 SF corner lot, offering 3,549 SF of beautifully curated living space with 4 bedrooms and 3.5 bathrooms. Designed by architect Hervin Romney, a founding member of Arquitectonica, the home reflects a distinctive architectural vision inspired by the organic principles of Frank Lloyd Wright and the expressive forms of Antoni Gaudí, where art, design, and nature seamlessly converge. This residence captivates with its abundance of natural light, soaring high ceilings, fluid open spaces, and harmonious lines that create a sense of warmth, sophistication, and effortless flow throughout the main living areas. The beautifully remodeled kitchen and bar are a true centerpiece, featuring high-end appliances, premium finishes, refined craftsmanship, and a design that balances functionality with striking aesthetics. Step outside into your own private tropical retreat, where lush landscaping, graceful curved terraces, and a stunning swimming pool create an atmosphere of tranquility and escape. This outdoor sanctuary is perfect for both relaxation and entertaining. As an added privilege, the property includes membership to the Key Biscayne Beach Club, offering exclusive access to one of Miami’s most coveted coastal lifestyles. Key Biscayne is renowned for its pristine beaches, charming restaurants, and vibrant yet relaxed atmosphere—delivering a true island lifestyle just minutes from the city.
Features
- Built-in Features
- Closet Cabinetry
- Cooking Island
- Fire Sprinklers
- Volume Ceilings
- Walk-In Closet(s)
- Den/Library/Office
- Utility Room/Laundry
- Open Balcony
- Other
Estimated loan & HOA
Loan payment and HOA only. Property tax and insurance are significant here and are not included.
- Principal & interest
- $27,700
- 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.
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.
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.