On the surface, the answer is obviously yes. 

As such, the only "deals" typically require extensive renovation, because anything that is purely surface level retail buyers will likely outbid you.  

Is the membrane secured to the parapet wall correctly?

They were popular because they were cheap, since your walls were also your roof.

It demanded to replace full flooring, scrape walls and repaint costing entire year worth of rent from that unit.Question: are there technical solutions inexpensive to remove cat urine instead of replacing all wood , carpet and walls?

I would have to replumb, run new electic, studs for walls, build a fire escape and so on.

In PA, basement habitation is not allowed if any basement wall is below grade or if the basement exit door to the outside is below grade (PA 6400.81).

. $30K should be more than enough for fresh paint and flooring and some other odds and ends, but if you need dry wall, cabinets, countertops, mechanicals etc it could get much pricier. 

It barely scratches the surface. 

If you look at the PadSplit website, they put up walls and convert the living room and dining room into more bedrooms, to fit even more people and get those high incomes.