Do NYC co-ops have to comply with GAAP

Boards don't have future projects costs estimated as the cost estimate is hypothetical, and why would anyone use a hypothetical in a income statement.
GAAP doesn't provide for hypotheticals of unknowns. Knowns yes, but unknowns no
Making up numbers makes no sense

My current coop does not follow GAAP in financial statements.

I think I have seen statements from some that do.

+1 to Admin -- how is a board going to know the future cost of roof work?

As a CYA, there's often a supplementary statement -- here's one from some old financials from Astor Court:

"Omission of Required Supplementary Information about Future Repairs and Replacements

Management has omitted the information about the estimates of future costs of major repairs and replacements that accounting principles generally accepted in the United States of America require to be presented to supplement the basic financial statements. Such missing information, although not a part of the basic financial statements, is required by the Financial Accounting Standards Board, which considers it to be an essential part of financial reporting for placing the basic financial statements in an appropriate operational, economic, or historical context. Our opinion on the basic financial statements is not affected by the missing information."

Board usually includes a statement in annual letter , such as :
-we expect to have a Local Law 11 (now known as FISP) inspection in xxxx years
-the boiler/chiller has life expectancy of xxx years before replacement

Our building's statements are audited to GAAP, and includes a note very similar to f_p's above. It notes that the costs have not been estimated, that this is required by FASB as supplemental information, and does not affect their opinion on the basic financial statements.

The technical details are important here: financials are audited to GAAP standards. The audit work only covers the basic financial statements. FASB says that the estimates should be done, but it does not affect the outcome of auditing the statements, and is supplemental. As Admin noted, the inclusion of hypotheticals is problematic in financials - this is part of the dubious behavior of many fin-techs of the last 20 years in presenting odd (e.g., non-GAAP) measurements of income and expenses and claiming that GAAP doesn't accurately reflect their operating model.

Failing to do the estimates is an issue of corporate governance, and if the numbers are calculated, should be included, but it's not 'required' under GAAP.

This is yet another example of how real estate in New York is different. Elsewhere some buildings undertake a capital reserve study that estimates these things and include that as part of the annual financial statements. Our NYC building does not.

My building board ran on doing a big investigation into building issues and paid for an engineer inspection so they could go sue the sponsor.. but then failed to do capital reserve study so the financials look the same as above.