3633 21st St
About This Property
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What does this mean?
Based on our analysis, the cap rate of this property is 1.25%. A negative cap rate indicates that the property might not be feasible as an income-producing asset. The median cap rate for a near zip code 11238 is 4.23%.
How much can I actually make?
Actual monthly rental income may vary between $4,760 and $7,140 depending on unit-specific characteristics. You can change the amount using the slider to further explore.
How is cap rate calculated?
Cap Rate = Net Operating Income (NOI) / Property Asset Value.
When calculating the cap rate, we assume 100% occupancy. Leverage (mortgage) is not considered.
Cap Rate provided by RealtyHop and RentHop, learn more about cap rate here.
Price History
| Date / Event | Date | Event | Price |
|---|---|---|---|
| Aug 4, 2026 | Withdrawn | - | |
| Withdrawn | |||
| Feb 6, 2026 | Listed | $10,000,000 | |
| Listed | |||
| Apr 18, 2025 | Listed | $11,500,000 | |
| Listed | |||
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Exquisite secluded sanctuary in the heart of Carolyn Heights. Tucked into one of Boulder's most prestigious enclaves, this estate offers a rare fusion of luxury, privacy, and relaxed sophistication . Set on a serene, tree-lined .81-acre level lot, this 7-bedroom, 5-bathroom oasis is where inspired design meets effortless living. Stunning views of the Flatirons awaken you each morning from your bed. Those same views tease your senses from the expansive patios with fully retractable doors that blur the lines from inside to outside. Bathed in natural light from soaring windows and skylights, every detail has been thoughtfully curated. Custom walnut doors and paneling welcome you into the home and invite you to explore. The chef's kitchen is a showstopper-featuring custom cabinetry, an oversized marble island, and top-of-the-line Thermador appliances. The open-concept layout flows seamlessly into a lush backyard oasis, perfect for gatherings or quiet moments of retreat by the fire pit. The primary suite is a haven unto itself with vaulted ceilings, a spa-inspired bath, spacious walk-in closet, and private deck access. With multiple flexible living spaces-including a dedicated home office and media room, this home is ready to adapt to your every need. Located moments from North Boulder's best hiking trails, cycling routes, farmers markets, and local eateries-yet nestled in the peaceful privacy of a mature, sought-after neighborhood. Elevated living starts here. LIVE BOULDER, LOVE BOULDER!
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| Jan 20, 2022 | Sold | ||
| Sold | |||
| Sep 30, 2021 | Listed | $4,950,000 | |
| Listed | |||
Phone: 425-283-2930
Address: 335 Madison Avenue, New York, NY 10017