Oh by the way, this often applies to any child under 6 just visiting :)3) First call to a lead remediation company which can examine and make recommendations.

However I think they are going to remedy this shortly.

Or a water damage / mold remediation company?

Some of the items will cost more to remedy than you have indicated. 

Anyone have experience with meth remediation?

I've been to small claims court, it's inexpensive but will take a day of your time, if you are concise on why you are there and what legal remedy you seek, you will likely prevail.Again, if it were me and they left the house clean and in good shape, I would send them the deposit and move on with my life.

(I am assuming you meant ceiling leak in lower unit, NOT actual roof leak from above the upper unit, leaking all the way to lower unit, since you were speaking about toilet issues.)8) Due to the leak ended up having sewage remediation company come out and rip out drywall, carpet, faming, and plumbing. 

I’d say you can remedy the situation with an inspection and your own contractor but if the neighborhood is awful you may just want to sell

I contacted the original HVAC tech that installed it but he's with another company, I had to call a new HVAC company to remedy it.

The other option is to delay closing or, hold back funds at close, until the situation is remedied.