When I had to replace a bedroom set, I called the rep I usually work with at the local furniture store, she sent me photos of things they had in stock, I had my handyman pick it up and deliver/assemble it.Storm/fire damage I fortunately haven't had to deal with, but I'd have insurance out there, a professional remediation company, and a contractor if necessary.  

Hopefully in your rehab budget you included mold remediation, frozen pipes, bad basement, and code violations as a few examples.

My favorite remedy that I heard if a renter loses his or her job...use the security deposit for next months rent.

I'm just wary because the lower unit hasn't been touched in 30+ years as far as updates, still has shag carpet, plaster walls, everything is dated but then again 100k owner financing with low down, I can afford to upgrade here and there when tenants move however the smoking tenant has been there a long time and I was planning on raising his rent some and hope he stays awhile since the unit already will need to be remediated. 

Not sure of the best approach to remedy this, other than pursuing some sort of legal action

Landlord can delead or "control" exposure within 90 days with expectation to delead in 2 years.May I draw on everyone's wisdom by asking - "What would you do if a.) you have the funds to remedy the problem and b.) you are short on funds?"

Hopefully you can pull this deal together and get everything remediated and get it up and running through the hard part. 

I had a mold remediation company checked right after, they do not see any warning signs except that they see the air is old, need to open the windows more to make sure the air is fresh.  

If I was asked to I'd remind them this situation was caused by their action and has cost me to remedy, and ask why they believe I should be reaponsible for their accomodations?

A petition for declaratory relief is simply a lawsuit that asks the judge to declare something, rather than awarding damages (a regular damages lawsuit) or ordering someone to do or stop doing something (request for injunctive relief)  or any of the other remedies such as quiet title, ejectment, mandamus, etc.