12 East 88th Street

The site is 100 feet wide and just over 100 feet deep, and the building occupies essentially all of it across thirteen stories with roughly 80,000 square feet of residential floor area. Those building totals do not establish average interior area or a comparison with the Carnegie Hill median. Verify apartment dimensions and landing arrangements from current plans, accounting for the documented combinations.

The stack runs from two townhouse units and three ground-floor residences at the base, through lines A to F on the middle floors, to four penthouses — PH11A, PH11B, PH12A and PH14 — at the top. The line gaps through the middle of the building (2A, 4B, 6B and 8C are all absent from the recorded schedule) are the signature of a combination-driven conversion; where two lines merged, one designation disappeared. It also means that apartments in nominally the same line can differ materially in size and layout from floor to floor, so square footage and floor plans must be checked residence by residence rather than by line.

Because the building is not landmarked, exterior work here is not subject to Landmarks Preservation Commission review — a genuine and underappreciated advantage on this streetscape, where neighbours a few doors west must apply for permission to change a window. It also means the façade program is entirely the condominium's own economic decision. DOB filings record façade repairs and structural work in 2016 during the conversion; a buyer should ask for the current Local Law 11 cycle status and the engineer's report regardless.

The condominium runs with union staff under a 32BJ collective bargaining agreement, and the amenity program was created during the conversion out of the former medical office space at the base. The building changed managing agents in 2018, from the firm the sponsor installed at closing to the firm that has run it since.

The audited financial statements on file for the condominium's first partial year show a building capitalized the way a well-structured conversion should be: roughly $1.45 million held in reserve money-market accounts at year-end against modest operating cash, funded by the sponsor's 3 percent-of-sales-price reserve contribution and by purchaser working-capital contributions. Two features of that statement deserve a buyer's attention. First, the condominium had not commissioned a reserve study or adopted a funding plan for future major repairs and replacements — the auditor noted the omission expressly. Second, the sponsor submitted a schedule of claimed costs of $658,949 for expenses paid on behalf of the condominium, of which the board recorded $393,143 after reviewing supporting documentation, leaving an unresolved balance the sponsor could pursue as a credit.

Both of those are 2017 facts about a building that is now nine years into operation, and neither is a red flag on its own. They are, however, precisely the questions to put to the managing agent: has a reserve study been done since, what is the current reserve position, has the sponsor claim been resolved, and are there any assessments in place or contemplated. Ask for the most recent audited statement and the current year's budget, not the conversion-era documents.

Ownership form: Condominium. Transfers proceed through the board's right of first refusal. Closing timelines run on condominium rather than cooperative terms.

Purchase application: Notwithstanding the right-of-first-refusal structure, the board reviews a substantial package. Per the application requirements on file, purchasers submit a financial statement with supporting bank, investment and retirement statements, personal, professional and bank references, a consumer-report authorization, a loan commitment letter where financing, income verification with pay stubs or a CPA letter, emergency contact information, the executed contract of sale, and signed acknowledgments including house rules, pet, window-guard and lead-paint disclosures. Entity purchasers add the certificate of incorporation, corporate resolution and operating agreement for an LLC, or the trust agreement for a trust, or the certificate of formation and partnership agreement for a partnership.

Pets: Permitted with consent, capped at two per residence, with the usual carrying-and-leashing rule in common areas and an express prohibition on pit bulls and other dangerous animals.

House rules of practical consequence: at least 80 percent of each residence's floor area (excluding kitchens, baths, closets and foyers) must be carpeted or otherwise sound-attenuated unless the board authorizes otherwise; no music or amplified sound between 11:00 p.m. and 7:00 a.m. if it disturbs neighbours; construction and renovation work only on weekdays between 8:00 a.m. and 5:00 p.m.; no roof access; no barbecuing except in areas the board designates; terrace planters limited by weight and requiring board consent above a defined size; and board approval required for any air-conditioning or ventilation installation.

Fees: the application, financing, document-retention and consumer-report fees, and the move-in and move-out deposits and fees, are set out under "At a glance" above and should be confirmed as current with the managing agent.

Flip tax or resale contribution: Not documented in the records reviewed for this profile. Confirm in writing with the managing agent before contract.

Recent sales

Recent closings at this building, from The Roebling Research Library. Prices are the transfer amounts recorded with the NYC Department of Finance; apartment-level detail is checked against the building’s own file in The Roebling Research Library before publishing.

Market read. Most recent trades (2026 to date) cleared a median $1,895/sf (floor-adjusted) across 4 sales. Floor-adjusted means each sale is restated to a constant mix of floors, so the figure can differ from the plain median of the sales listed above. Median listing discount 7.1% from the last ask — a recurring negotiation gap worth pricing into any offer or listing strategy.

Sales sourced from NYC Department of Finance recorded transfers (BBL 1-01499-7502; each condominium apartment is its own tax lot). Apartment-level facts (line, condition, asking-price context) curated and cross-verified in The Roebling Research Library. Not all transactions cross-verify with ACRIS records — sponsor and LLC purchases sometimes record at stipulated values rather than market price; square footage from recorded condo declarations and offering plans.

Ask whether the residence is vacant. This is the first question, not the fifth. Twelve residences left the sponsor as a bulk package in July 2017 and have been resold individually since. A price well below the building's other sales may reflect a tenant in place; obtain the lease, rent-regulation status and possession terms for the specific apartment before treating it as a vacant-unit comparable.

There is no abatement, and there never was. Underwrite the full tax bill from day one and compare monthlies against abated new-development inventory accordingly. The True Monthly Carrying Cost Calculator is the honest way to do that comparison.

The building is not landmarked — check the map before you assume it is. Neighbours on the same tax block sit inside the Expanded Carnegie Hill Historic District; No. 12 does not. That is an advantage for exterior work and a difference from almost everything around it.

Get the current financials, not the conversion-era ones. The first-year audit noted no reserve study and an unresolved sponsor cost claim. Ask what has happened since: reserve position, reserve study, assessments, Local Law 11 status, and whether the sponsor claim was settled.

Check the residence, not the line. The combination program means apartments carrying similar designations can differ substantially in size and plan. Verify square footage and layout against the recorded declaration for the specific unit.

Position against the co-ops, not against the towers. The building's argument is prewar scale as a condominium on a Carnegie Hill side street — no co-op board admission, with purchases running through the condominium's application and right-of-first-refusal process; confirm financing and ownership-entity rules in the current declaration, bylaws and house rules. That is a real differentiator to the buyer who has just been turned down or slowed down by a co-op board.

Separate your comparables before the buyer's broker does. If occupied-unit transfers are sitting in the building's recorded history alongside your line, explain them proactively. Left unexplained, they become a negotiating tool.

Lead with the layout. A combined full-floor or half-floor plate in a 1931 building is the product. Floor plans and ceiling heights do more work here than the amenity list.

Have the building's paperwork assembled. The offering plan, by-laws, house rules and the most recent audited financials are on file with us and should go to serious buyers' counsel early. Providing the documents early can assist counsel’s review; it does not establish a particular time saving.

• 60 East 88th Street — the block's other condominium, boutique and postmodern; the closest direct alternative for a Carnegie Hill condominium buyer.
• 2 East 88th Street — the Fifth Avenue corner co-op on the same tax block, inside the historic district; the ownership-form contrast.
• 4 East 88th Street — prewar co-op two doors west, same block, landmarked.
• 19 East 88th Street — Carnegie Hill prewar co-op directly across the street.
• 1060 Fifth Avenue — the block's Fifth Avenue anchor; the top of the local co-op market.
• 1067 Fifth Avenue — boutique Fifth Avenue co-op on the same block.
• 1010 Park Avenue — Carnegie Hill condominium, a newer-construction pricing contrast.
• 1050 Park Avenue — Carnegie Hill prewar co-op of comparable scale.
• 1088 Park Avenue — the neighbourhood's architectural co-op benchmark, on Park Avenue.
• 1130 Park Avenue — Carnegie Hill prewar co-op, larger-layout comparable.