whatever can go wrong will.... I personally would not do it, if something breaks and as we all know something will break, who is responsible, also consider wear and tear. you might also have liability as a landlord (if you do proceed I would get advice from my insurance agent, etc). I just think it is a bad idea in general, but if your friend has no other options you need to do what is best.
2007 Chevy 2500HD CC
2010 V-Lite 30WRLTS
Nights Camped 2011 -64
Nights Camped 2012 -50
"I Live in My Own World, But It's OK. They Know Me"