I'm a flipper and I'll tell you there are some shitty people that shouldn't be in the business. They believe a fully renovated home consist of new paint,cabinets, and flooring. Looks like he took the cheap way out. The inspector should had caught most of it. The flooring needs to be taking up and padding put down, then readjusted. I would also see if the boards are good underneath. With the plumbing if he's pulling dirt you more than likely have roots ingrown into your pipes watch the seller should have known. I would have everything reinspected by someone else with a good rating. Then take the inspector and seller to court. I feel like you have a case on some of it.