You can go to the extend of using one access point per room with the low power dual band AP that fit in a wall outlet, mainly use in the hotel setting.

Probably worth having a master electrician check all the electrical including outlets and wiring, as there's a good chance you could be looking at rewiring the whole house if it has aluminum wiring, knob and tube, a fuse box, ungrounded outlets, or any other dangerous outdated stuff.  

Bonus with the walls being down to the studs with the plaster removal is that we can add in extra power outlets and in more convenient locations.The delay is mostly my fault...

I’m also trying to get out of the medical field (I‘m a Physician Assistant).I’ve had my eyes on a 2-family here locally for some time but don’t have the capital to buy it myself... if you want to check it out let me know.

They operate like a broker (lots of outlets, which means more programs than a bank and often lower rates), but they are the direct lender (which makes them a bit easier to work with and more predictable/reliable compared to a broker). 

For the Electrical, it sounds like they tried to hook up a generator to test the house but were unable, possibly due to missing/damaged wiring or outlets. 

Add a new outlet?

You plug it in to the same outlet the old one was plugged in to.

As far as the GFCI outlet goes, that may not need to be installed if the breaker the line is on is a GFCI breaker? 

The outlet looks old and the hose bib looks new.