Some of the the things I would look for:Are the floors levelCracks in foundationRoof qualityCracked roof joist or wall studsWeird electrical junction boxesFunky plumbing... pvc pushed into cast iron pipes... cracks in piping

My wife and I are in process of purchasing a Quadplex built in 1940s and currently has baseboard electric heat, and window a/c units.

@Bjorn AhlbladThe roof is in good shape and each unit has a separate water and electricity meter.Each unit is 2/1 and there is hook up for washer drier but the actual washer drier is not provided.

I have seen this many times for water and electricity.

We doubled the rents, but upgraded the furnace (it needed it), HW tank from electric to NG & gave them a scratch & dent stove, washer & dryer that we keep in stock.

I have learned a TON about the investing game and I've been bitten by the REI bug myself. 

Here is a standard for 900-1200 sqft row homes in Philly depending on the neighborhood and assuming nothing is wrong with the foundation:South Philly/West Philly West of 52nd Street: 75-85k (contingent upon underpinning basement which is big expense)-Complete gut, redo electric and plumbing, dig the basement, redo everything, Central AC, turn a 3/1 into a 3/2 or 2/2 w/ a master suite higher-end finishes, touch facade.Germantown Close to Germantown Ave/ Cobbs Creek/ West Oak Lane Close to Cheltenham / Better pockets of Olney: 60-70k-same as above but you do not necessarily have to underpin the basement.

Not a bug deal though.

If your GC is literally doing everything himself and only subbing out HVAC, electrical and plumbing then perhaps he can hit that number...

The question de jour is “has there ever been a bed bug problem in this house?”