You need to be patient in real estate, and especially dealing with the city.One of my properties is vacant for almost half a year now due to permit approval delays from the city.

So I think this one, while odd and probably not the easiest to resell, will cash flow like crazy.

If you're fixing this to flip, I'm not sure why you care about all of that information anyway - all old houses have a history; sometimes there's good reasons for why things were done - I have found this out in virtually every interior soffit I thought I would tear out - and sometimes it was just the cheapest/easiest thing to do at the time.

Easiest solution may be to just install an additional layer of soundblocking drywall on the existing 1st floor ceiling, but don't know how effective it will be

The lady who stayed, love the house and want to start a new lease and have new housemates as she can’t pay the whole rent (she paid half the rent end of June).

It is actually for sale the owners had the property for almost half a century I am in the middle of finding everyone needed for the project before I fill out the application for private money.

I'd say close to half don't even ask me what updates I did to the property unless I volunteer the info. 

The rental seems the easiest way.

The only smooth FSBO transaction is one where the buyers agent does the work for both sides for only half of the usual pay.  

That imo is by far the easiest and cheapest way to get a portfolio.