If you home does not meet habitability standards by your local municipality (like the health department) he is required to make it so that it is. I would call your local health department and explain to them the situation. They should be able to give you more insight.

If you do the work yourself, make sure you negotiate compensation ahead of time. Get it in writing, but if you are suspicious that you MIGHT have to take him to court, don't do the work at all. Repair projects like yours can turn into a full time job and if you have to then turn around and chase him through the courts, that's even more money and time spent.

Better to keep it simple. If he won't do the work (which he hasn't), then its time to get out.

Yes, they have to answer to the building inspector, I would try calling in the building inspector and making sure he does a thorough inspection, because if your landlord doesn't comply he can face fines.

call sanitation hope you have a lease get the cirtificate of occupanyin the town hal lrecords its open to public see if its leagal who lived before and whattheypaid your landlord legally may owe you money! GEt a legal aide free lawyer take the #@!&$%* to court Dont make repairs you'll get shafted when you deduct the price from rent and they will insist they had no ide or you didnt ask theyl lmake up a reaction Slumlords are all the same where ever you go