There was a proposal need the end of Bloomberg administration to sell project parking lots(!), mostly in Manhattan, to developers that would build market rate housing. The money would then be used for capital repairs. The plan was bitterly opposed by residents who apparently value massively subsidized parking over non-falling-down buildings and/or believe that the money is going to magically appear in some other way. DeBlasio has put out a modified version of the same plan, it involves a mix of "affordable" and market rate apartments being developed on the same parcels. That of course, will mean less money for NYCHA, which means fewer repairs, but I guess he doesn't care.
Personally, I think it makes the most sense to sell outright a few of the most valuable properties and use the money to make the necessary capital repairs on the rest of the system. If enough of those empty apartments can be fixed up, it might not even be a net loss of public housing.
1 http://www.nytimes.com/2014/08/12/nyregion/new-york-public-h...