If it's not too bad then you may be able to get the roof 'certified' by a roofing inspector.

A good inspector will find those though and it's just something to be aware of, not a rampant problem at all.

We had to open walls for inspectors to approve work on a bathroom that was never permitted in our home. 

If so they have plenty of home inspectors and in many states (IN is) this is a licensed and regulated field.

With a HML each time they fund a repair they send an inspector out and then give you draws each time.

Maybe hire a Home Inspector with construction experience. 

Since I have done two live-in flips I also have a network for contractors and inspectors.  

The inspectors were very helpful.

I have a professional home inspector doing in the inspection but I figure spend my time productively and I'm building a checklist for myself for things I can look for as well.

I think having a contractor instead of "professional inspector" to do the inspection is a great idea, for 1)a good contractor is probably more knowledgeable than an inspector, and 2)you get a detailed quote at the same time.