What do I do if apartment is inhabitable?

Of the things you mention, only a bad infestation would qualify as uninhabitable. Once a law firm is involved you may wish to enter into a Stipulation which frees you from liability for rent in exchange for a timely move out.

If the unit was truly uninhabitable, then the landlord has "constructively evicted" you and you would owe no rent after you left. Unless the owner or their manager engaged in the sexual harassment, the owner would not be responsible for that, and probably not the drug usage. ?If the windows allow entry into the unit because there is no lock, you would have a weak argument the unit might be uninhabitable. ?You do not indicate how bad the cockroach problem is. I presume you moved out and stopped paying rent before the 30 days was up. The best thing would be to speak to the landlord and point out all the problems and his failure to respond, even though some things could be remedied for just a little money, that if he goes to court you will fight his right to recover any rent and will present a Green defense seeking some of the rent back for the defects, and that no matter the results he will end up paying his attorney more than the matter is worth [is there an attorney fee clause in the rental contract?]. Point out the major thing he wanted was that you be out, and that has occurred.