905 West End Avenue

The building carries roughly 102,000 square feet of residential area across thirteen stories on a lot of about 11,600 square feet, with a 115-foot frontage. Those building totals do not establish an apartment’s usable area or price advantage. Inspect the individual plans for entry galleries, separation of entertaining and sleeping areas, and room dimensions, and compare actual sales. Listing records describe roughly a dozen distinct configurations, from classic-six layouts to four-bedroom residences, generally between about 1,600 and 2,300 square feet.

The corner siting at West 104th Street gives the building two full street elevations, so a significant share of the residences carry corner exposures and cross-ventilation rather than a single orientation. Upper floors on the west side pick up open outlooks toward Riverside Park.

The 2018 combination of two apartments — filed with DOB together with the merger of their tax lots — is the reason the offering plan's 54 units and the current roll's 53 do not agree. That is a documented, ordinary reconciliation, not a data error, and any valuation should check which count and floor plans its data use.

905 West End Avenue runs as a staffed prewar building rather than an amenity building. The first-year operating budget in the plan on file carries a resident manager, porter and doorman payroll, an elevator maintenance and consulting contract, roof-tank maintenance, standpipe testing, boiler cleaning and water treatment, and a contract-operated laundry in the cellar. The programme today is the same in kind: attended lobby, laundry room, and — added by the condominium in 2018 under a Department of Buildings alteration application — a roof terrace and garden.

The capital record since conversion is active, though filings alone do not confirm completion or current condition. The sponsor filed to renovate the lobby and public hallways on floors one through thirteen in 2008, with facade cleaning and roof system replacement the same year. Facade work recurs through the following decade: minor repairs in 2010, further work in 2013, and sidewalk sheds in 2013, 2015 and 2016 for remedial repairs. The heating plant was upgraded in stages — the gas portion of the dual-fuel burner activated in 2014, a new chimney liner and boiler breeching in 2015. Structural upgrades to the roof were filed in 2017, ahead of the 2018 roof terrace.

Two operational cautions follow. First, the recurring facade cycle in a thirteen-story masonry building is a capital-planning item whose cost relative to other projects requires engineering estimates and the reserve plan, and since 2015 it runs through LPC review as well as DOB. Second, the current ownership concentration and expense allocation require updated records; read the current audited financial statements, the reserve position, and any live or recently concluded assessment rather than relying on the common charge alone.

Of the 53 residential unit lots, 40 have been individually deeded at least once; 13 have never transferred to an individual buyer in the recorded chain. On a single day in November 2020, nine unit lots transferred together in one bulk transaction at per-unit consideration far below the individual resale range in the building — a bulk transfer whose occupancy and encumbrances require transaction documents, not an inference from consideration alone.

None of this makes the building a rental wrapper. Individual apartments have been bought and sold by separate owners continuously since 2009, including resales recorded in 2023, 2025 and 2026, and the condominium is a functioning for-sale building. But a buyer should understand what the mix means in practice:

• Board composition and voting are influenced by whoever holds the unsold and bulk-acquired units.
• Common charge collection and reserve funding rest heavily on whoever holds the unsold and bulk-acquired lots. Every unit owner owes common charges whether or not the apartment is tenanted; ask for the arrears history and how many lots any single owner holds.
• Rental occupancy requires a current unit schedule. Deed history does not establish which apartments are leased or how occupancy affects common-element costs; review the budget and audited statements.
• Financing on individual units can be sensitive to owner-occupancy and concentration ratios; a lender may ask for them, and the answer here is not the default one.

Ask the managing agent for the current count of sponsor-held and bulk-held units, the owner-occupancy percentage, and the concentration of ownership by any single entity, before contract. This is the single most useful question at 905 West End Avenue.

Ownership form: Condominium. Purchases close through the Condominium Board's right of first refusal rather than cooperative board approval. The right of first refusal in the plan on file applies to leasing as well as sale.

Pets: Permitted. The house rules in the plan on file allow dogs, cats, birds and other common household pets that do not create a nuisance, health hazard or unsanitary condition, subject to Condominium Board consent and to the owner indemnifying the condominium. Confirm any weight or breed rules adopted since.

Subletting, pied-à-terre, LLC and trust purchasers: Not documented; confirm in the declaration, bylaws and house rules. Leases are subject to the Board's right of first refusal; minimum lease terms should be confirmed with the managing agent.

Rent-regulated tenancies: The 2009 conversion plan recorded protected tenancies; their current status requires updated unit-specific records. A buyer purchasing a tenant-occupied unit, or evaluating the building's income profile, needs the current regulatory status of that specific unit in writing.

Flip tax: None appears in the plan on file. Confirm whether any resale capital contribution has since been adopted.

Landmark constraint: The lot has been inside the Riverside–West End Historic District Extension II since 2015. Window replacement, facade work, storefront changes and rooftop equipment may require LPC approval; permit categories and exemptions depend on the scope, and a Certificate of Appropriateness is not required for every exterior project.

Real estate taxes: The assessment roll shows no exemption; check and underwrite the current bill on the specific unit lot.

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 $1,223/sf (recorded) across 2 sales. Median listing discount 3.2% 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 1-01891-7502; 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 for the owner-occupancy and sponsor-held counts in writing. Thirteen of fifty-three unit lots have never been individually deeded, and nine more moved in a single bulk transaction in 2020. Your lender may ask; you should ask first.

Read the offering plan and the current financials together. The plan on file establishes the structure — non-eviction conversion, sponsor rental rights, house rules, the resident manager's unit. The audited statements establish where the building actually stands on reserves, assessments and the facade cycle.

Reconcile the unit count. The plan offered 54 residential units; the Finance roll carries 53. The 2018 apartment combination explains it. Check which unit count and floor plans an analysis uses before relying on it.

Price the landmark constraint. Designation arrived in 2015, after the conversion. Review later amendments and current LPC requirements; the scope determines whether approval is needed and which permit applies.

If the unit is tenanted, get the regulatory status before contract. The 2009 plan recorded rent-controlled and rent-stabilized tenancies; it does not establish which remain today.

If you're considering 905 West End Avenue, also evaluate:

• 885 West End Avenue — a Gaetano Ajello building on the same stretch of the avenue; the closest architectural sibling
• 895 West End Avenue — the third of the Ajello group nearby; same architect, same vintage, different tenure
• 915 West End Avenue — immediately north on the same block; the adjacent prewar alternative
• 890 West End Avenue — directly across the avenue; comparable prewar scale
• 871 West End Avenue — prewar West End Avenue building a few blocks south
• 845 West End Avenue — the same corridor at a slightly different vintage and service level
• 801 West End Avenue — larger prewar building on the avenue below 100th Street
• 600 West End Avenue — the mid-avenue prewar benchmark
• 11 Riverside Drive — the Riverside Drive alternative for buyers weighing park frontage against avenue frontage