HDFC Income Restrictions

I think the income restrictions apply as long as you own the apartment.

No, once you buy you're in.

No affordable-housing program I know of has a disincentive to earn more money. Many take 30% of gross income, so it quickly becomes more desirable to move to nicer housing. But I don't know of any HDFC that has a sliding scale for maintenance, and it's probably illegal (equal treatment for all shareholders) -- but I'm no lawyer.

I should add that many HDFCs have other unattractive features. Make sure you take a fine-tooth comb to the finances, the physical condition of the building and its systems, the current liabilities of rent-regulated tenants (which are also future bonuses, because when they die the apartment becomes a market-rate asset to be sold or rented out by the coop)

But most of all learn exactly how the flip tax works, and consider both up and down markets.

On the other hand, find out when it became an HDFC, and when/if the income restrictions can be removed (by vote of the board or the coop's owners).

And -- listen carefully -- NEVER EVER trust any advice from the diabolical self-serving "nonprofit" UHAB/SHUHAB.

Get a good lawyer, preferably one who really understands the HDFC programs.