There were exposed water lines and pipes in the rooms and missing doors.

I had an estimate done ($7k) because at this point the sprinkler piping is exposed and I'm afraid that could lead to an even greater problem.

Now we are more selective.The worst were those with flea infestations, flooded basements, burst pipes throughout & then mold remediation. 

Hot water heater, furnace, gas, electrical box, HVAC, oil tank, plumbing pipes.

The property was built in 1940 and has cast iron piping.

Exhausting. :-) 

We relocate tenants if there is a hazard,  always use your own home as a guideline would you move out to get new floors probably not, now if a pipe burst and created mold you probably would. 

Nobody flirts with idea of SEC up tail-pipe for the fun of it. 

If it exist, it's usually on SFH under $180k, and at that point, the profit is so little, it's not worth the headache.I have clients with portfolios of 15+ single families in this range, and to see them pocket $200-300/month is exhausting lol.One maintenance request erases 6 months of cash flow.

I’ve been in this building for 5 years and have only had one real issue where a pipe burst due to -20 degree weather.