Certainly learning a bit how to spot the for sure items like the '50s 8 inch square floor tile with the associated black mastic, the heating ducts covered in thin white "insulation" as well as attics with the vermiculite insulation gives you a running start by knowing you have to add funds to rehab budget.

Granted, the neighborhood wasn`t great(Mastic/Shirley area), but I would`ve beenwaaay ahead of the game.

Other things are: white fabric ductwork tape, vct tiles (9x9), mastic for the tiles, vermiculite insulation to name a few. 

One company said to do some mastic and foil tape sealing in the ducts in the basement to fix.

EACH piece needs back buttered as well as wall then applied and spaced and the thinset (NOT MASTIC) scraped out of grout joints. 

This paper is a medium mastic, repositionable, which was good, because there were a few times I had to reposition it.

Technically you should use a product such as stego mastic then cover it with stego wrap (a vapor barrier plastic sheeting that is basically rip proof) This must be from the top to the bottom and it will not be cheap.

Many of the older vinyl floor tiles and any associated paper-like backing, mastic, adhesive or glue, may contain asbestos.

Metal in the valleys with mastic. 

... also in floor mastic, ceiling tiles, wiring, caulk, window glaze, insulation, and a whole host of other things I'm likely forgetting.