My dad lives up there and we do stuff together and I'm happy to send him by to give you a second opinion on the renovation.Sounds like a pretty good deal on the surface.

The way I see it on the surface, I'd be better off buying a $400k (ARV) house at 75-80% ARV than a $160k house at 70% (ARV); I'd have a more desirable house with a larger net profit, and if things went sour during the rehab I'd be able to get out from underneath it easier, being that that type of home is more in demand (therefore less risk in that respect).

Now all this crap surfaces.

Take a hard look at the properties for slip, trip, and fall hazards; loose and missing electrical or plumbing fixtures; obvious leak sources- roof, supply piping, or sewage; exposed wiring; adequate lighting in all common areas; fire hazards; sources of combustion gases; pest infestations; peeling and cracking painted surfaces; loose or flaking insulation or other coatings; inadequate electrical, water, or other utility services.Deal with the obvious first.

i've only scratched the surface about commercial.

You are correct in that you should keep surfaces with lead based paint intact.

Although, from my experience, you're only going to "scratch the surface" as they say.

And only in the last couple years that the "2 year minimum" surfaced. 

We are doing a historic re-use on our project (for the tax credits), using muni revenue bonds to finance construction and doing an extreme green build out (solar, rain water collection, auto electric , bio parking surfaces--again more tax credits and lower long term operating expenses).

Fill the gap with wax and level the wax from flange out over the surface of the flooring so there is nowhere for water to go but onto surface of flooring should a leak develop.