If you're worried about cracking, use a crack-isolating membrane like Kerdi. 

That income can be used but its an isolated circumstance.The only program on conventional that allows the use of boarder income outside of the exception i mentioned above is MCM- My community Fannie Mae but it requires the borrower make under the area median income (depending on county) and has no other properties owned at the time of funding.I work with many investors who house hack on the lending end and have personal experence in house hacking as Brandon would call it. 

The benefit is that you isolate the liabilty of one property to that one property - so if you're getting sued by a tenant they sue the owner of that property, and if that owner is an LLC that only owns that one property, your exposure is only that one property.However, there are loopholes that a clever attorney can use to get around or through the corporate veil.  

This is a very complex subject and an unpopular one for some so I won't go any further other than to say that you can't just look at a neighborhood in isolation. 

isolation between personal asset / properties of different LLCs;  2. 

The routers we use are capable of both layer 2 & 3 segregation and we provide each unit with its own isolated network segment.802.11 (WiFi) becomes problematic as the size of the building grows:  if you have 6-tenants, each with their own personal WiFi network the interference is tolerable, but once you scale to a 20+ units the tenants access points will be fighting with each other and there will be a lot of RF noise.

Also, in my experience bad things don’t happen in isolation.

Some people LIKE to live in more isolated areas, and this house might be just the ticket.

Keep in mind it's very isolated from the rest of us; hard to check on your property manager, if you can find a decent one. 

Not to say there aren't some jurisdictions or isolated incidents that could be different, but that could happen in any state.