The worst area was around an outlet where he thinks the fire started.

Disconnected outlets in succession and trial and error to try and find the short.

Owning a total of at least 16 units will make any unoccupancy, especially unexpected, will make any less painful. 

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the whole house if it has aluminum wiring, knob and tube, a fuse box, ungrounded outlets, or any other dangerous outdated stuff.  

I was reading Brandon Turner’s Book On Rental Properties and in Chapter 18 he said that there will be many things that would come up from tenants that are unexpected.

Luckily, I set aside a portion of the monthly rent for unexpected repairs/issues.

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.

There are lots of ups and downs and unexpected twists and turns. 

It all depends on whether you want to guess from the exterior, or break laws by trespassing and door knocking.5. the usual unexpected repairs seems like another thing to add.Are you opposed to wholesalers?