We're in the process of buying a home and just went through inspection. Of all the issues found, I believe this to be the most serious. There is a deck resting on a concrete slab. Part of the slab is heavily fragmented. Another section of the slab has cracked, settled, and is now sloping toward the house. There's no obvious foundation damage, but there is what looks to be a retrofitted drainage system setup.
Looking for input in two main areas. First, how serious is/could this be? Something that needs to be addressed within the next five years, or something that we shouldn't even consider closing on until it's fixed? Second, what's involved in actually resolving the issues? We know that the deck construction itself has issues, so that's a separate thing.
The files I have are large, so here's a gallery: http://imgur.com/a/mmUXM
You can see a paint line on the house which shows how far down the slab has settled.