Copper wire conductors in NM sheathed cable or in rigid metal or PVC plastic conduit has been the norm since the mid-1970s, and there are currently no new innovations in the wiring materials themselves.Most houses I have issues are from the 1950s old rag wire with no ground the cloth is brittle from heating of the current over the years.Lots of flippers will cobble together a house, install new wire where they are forced too leave old rag wire to rot away.

It'll look like the glorified vinyl linoleum flooring it is, but hey, that's the price you pay for hands-off real estate investing, and lots of people like plastic everything in their lives.Ripping out a whole subfloor because of cat pee, as @Micah Mcarthur suggests, seems a bit much.

Could not really store anything in it that was not in plastic garbage cans.

Cardboard and plastic takes up a lot of negative space in the trash bins.

Step #1 - Put something (i.e. tarp, drop cloth, plastic sheeting, etc) down on the floor to help catch the mess and make for an easy cleanup.Step #2 - Fill a sprayer up with water and spray it on the popcorn ceiling. 

We've never offered cash for keys, but we have offered moving boxes, tape, 3-mil plastic bags, helpers with a truck, etc.

I would not worry about attaching a sheet of plastic to the studs, if that is what you mean by a vapor barrier.

What I would do is check your basement floor first by putting a 3 foot by 3 foot piece of clear plastic down on the floor first and tape around all corners.  

the little plastic tab on the leg was busted and a nail head protruded. 

That stuff is foam plastic?