Depends on the foundation, plumbing, electrical and roof.

This time through I saw that he had completed a lot more of the work and had gotten a new roof.

Empty can be good for you if you need capital improvements that are inconvenient for a tenant like parking, roofing or electrical. 

Such as missing roofing tiles, sagging ceiling, cracks in the foundation etc.  

I have done repairs for other investors due to home inspection things as simple as adding an attic fan, to repairing roof leaks that were obviously there way before the rehab, to ripping out an entire bathroom, and starting from new.  

Not to rough inside but it does need a new roof  and gutters ASAP and Central heat and air installed.  

and i havent ruled out contacting Los Angeles Child Services because in a way, now that i have been told by the mother's mother than there was fraud involved in regaining custody, doesn't 'see something, say something' apply especially when its going on under one's own roof?

The roof was partially gone, so it flooded during the next rain.

Owners often look to sell just as lots of things are approaching replacement: mechanicals, roof, windows, outdated units.

I hired a general contractor for replacing roof, remodel kitchen and bathroom along with painting and some other work. the whole project is about $ 65k which include materials and labor with a payment schedule . he's been very slow and for three months not getting much done due to he's having a few jobs at the same time .