501 Bay Ln
Key Biscayne, FL 33149 · single_family · For Sale · 9 days on market
Asking price$5,990,000
5 beds 5 baths 4,759 sqft
Listed by Brigitte Nachtigall · One Sotheby's International Realty
Typesingle_family
Built1995
Price / sqft$1259
Est. value (own analysis)$6,808,919
Rent estimate (own analysis)$28,000/mo
HOANone
1 / 42
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Statusfor_sale
Listed date2026-08-24
Removed date—
MLSMiamiMLS #A12074814
Coordinates25.69227, -80.17289
Address501 Bay Ln
CityKey Biscayne
StateFL
Zip33149
Listing ID6113672216
Sourceus-real-estate-listings, cached 2026-08-31
ZIP market snapshot (33149)
Typical home value (ZHVI)$1,692,135
Typical rent (ZORI)$7,910/mo
Zillow Research's ZHVI (home value index) and ZORI (rent index) for this ZIP, as of 2026-07 — free published data, refreshed monthly, no RentCast quota spent. "Typical value/rent" is a smoothed index, not a literal median of active listings.
Underwriting (buy-and-hold, default assumptions)
| Acquisition (one-time, not monthly/yearly) | |
| Purchase price | $5,990,000 |
| Down payment (20.0%) | $1,198,000 |
| Loan amount | $4,792,000 |
| Closing costs (5.0%) | $299,500 |
| Total cash to close | $1,497,500 |
| Income | |
| Rent (comp-derived) | $28,000$336,000 |
| Vacancy loss (8.0%) | |
| Effective gross income | $25,760$309,120 |
| Operating expenses | |
| Property tax (placeholder 1.9% of price) | $9,484$113,810 |
| Insurance (placeholder 0.8% of price) | $3,993$47,920 |
| HOA dues | $0$0 |
| Management (0.0% of EGI) | $0$0 |
| Maintenance (5.0% of GSR) | $1,400$16,800 |
| Total operating expenses | $14,878$178,530 |
| Net operating income (NOI) | |
| Debt service & reserves | |
| Debt service (6.66%, avg 30yr rate as of 2026-08-27, 30yr amortizing) | |
| CapEx reserve (5.0% of GSR) | $1,400$16,800 |
| Mortgage insurance (PMI) (0.0% of loan, not required — down payment ≥ 20%) | $0$0 |
| Cash flow |
Cap rate
Cash-on-cash
DSCR
Rent-to-price (1% rule)
Gross rent multiplier
Operating expense ratio
Break-even occupancy
Comparables
Same ZIP. Real active rental listings, used to derive the rent estimate above.
| Address | Type | Beds | Baths | Sqft | Asking rent | Listed | Days on market |
|---|---|---|---|---|---|---|---|
| single_family | 5 | 6 | 3,650 | $28,500 | 2026-05-19 | — | |
| single_family | 5 | 6 | 5,421 | $25,000 | 2026-08-03 | — | |
| single_family | 5 | 6 | 3,495 | $20,000 | 2026-06-10 | — | |
| single_family | 5 | 6 | 3,661 | $55,000 | 2026-07-20 | — | |
| single_family | 5 | 5 | 3,202 | $40,000 | 2026-03-28 | — | |
| single_family | 5 | 6 | 3,633 | $21,500 | 2026-05-21 | — | |
| single_family | 5 | 6 | 5,341 | $70,000 | 2025-05-26 | — | |
| single_family | 5 | 5 | 3,149 | $22,000 | 2026-07-01 | — | |
| single_family | 5 | 7 | 3,475 | $27,500 | 2026-05-21 | — | |
| single_family | 5 | 6 | 4,700 | $35,500 | 2026-03-18 | — |
Same ZIP & bedroom count. Closed sales from Realtor.com over the last 12 months, matched to this property's type — real transaction prices, not asking prices. Falls back to Miami-Dade County public records (property appraiser tax roll) when Realtor.com has no sales on file for the area.
| Address | Type | Beds | Baths | Living sqft | Sale price | Sale date |
|---|---|---|---|---|---|---|
| 346 Gulf Rd | single_family | 5 | 6 | 3,285 | $4,700,000 | 2026-07-27 |
| 677 Hampton Ln | single_family | 5 | 4 | 2,429 | $3,125,000 | 2026-03-09 |
| 670 Allendale Rd | single_family | 5 | 5 | 2,320 | $3,475,000 | 2026-01-27 |
| 261 Greenwood Dr | single_family | 5 | 6 | 3,525 | $6,275,000 | 2025-12-11 |
| 201 Buttonwood Dr | single_family | 5 | 5 | 3,791 | $5,265,000 | 2025-12-09 |
| 100 Hampton Ln | single_family | 5 | 6 | 3,584 | $6,200,000 | 2025-12-04 |
| 220 Cypress Dr | single_family | 5 | 6 | 4,089 | $4,600,000 | 2025-10-10 |
Same ZIP. Other properties currently for sale nearby — asking prices, not closed sale prices. Not a price comp; see Sold comps for actual transaction history.
| Address | Type | Beds | Baths | Sqft | Asking price | Days on market |
|---|---|---|---|---|---|---|
| 485 W Matheson Dr | single_family | 5 | 9 | 11,528 | $237,000,000 | — |
| 520 S Mashta Dr | single_family | 5 | 4 | 3,085 | $19,900,000 | — |
| 571 Glenridge Rd | single_family | 5 | 7 | 3,768 | $7,490,000 | — |
| 545 Sabal Palm Dr | single_family | 5 | 5 | 4,166 | $7,950,000 | — |
| 24 Grand Bay Estates Cir | single_family | 5 | 6 | 4,220 | $4,950,000 | — |
| 524 Warren Ln | single_family | 5 | 4 | 2,700 | $3,730,000 | — |
| 445 Grand Bay Dr Ph 1A | condos | 5 | 6 | 8,435 | $18,900,000 | — |
| 445 Ridgewood Rd | single_family | 5 | 6 | 3,688 | $6,685,000 | — |
10-year hold projection
IRR-1.4%
Equity multiple0.77x
Total return (10yr)$433,411
| Year | Property value | NOI | Cash flow | Loan balance | Equity |
|---|---|---|---|---|---|
| 1 | $6,169,700 | $130,590 | -$255,746 | $4,740,044 | $1,429,656 |
| 2 | $6,354,791 | $135,400 | -$251,356 | $4,684,520 | $1,670,271 |
| 3 | $6,545,435 | $140,377 | -$246,809 | $4,625,184 | $1,920,251 |
| 4 | $6,741,798 | $145,526 | -$242,101 | $4,561,772 | $2,180,025 |
| 5 | $6,944,052 | $150,854 | -$237,227 | $4,494,007 | $2,450,045 |
| 6 | $7,152,373 | $156,364 | -$232,179 | $4,421,587 | $2,730,786 |
| 7 | $7,366,944 | $162,065 | -$226,954 | $4,344,195 | $3,022,750 |
| 8 | $7,587,953 | $167,963 | -$221,544 | $4,261,487 | $3,326,465 |
| 9 | $7,815,591 | $174,063 | -$215,943 | $4,173,101 | $3,642,491 |
| 10 | $8,050,059 | $180,372 | -$210,145 | $4,078,644 | $3,971,415 |
Assumes 3.0% annual rent growth, 2.5% expense growth, 3.0% appreciation, and a 6.0% selling cost at exit — all placeholder assumptions, not market-derived.