Hi Paul,
The main risk with buying a wholesale property is that they're usually sold as-is with no contingencies. Unless you are confident in estimating the renovations needed, I would highly recommend getting a contractor's professional opinion of the rehab costs. Ask your contractor to walk the property with you if they're available during the showing, or at least send them the photos and information that you received from the wholesaler to get their opinion.
In Pittsburgh a light or cosmetic renovation is about $20k, medium is $50k, and a full gut is $100k. You can get some estimates from contractors for what they charge for big ticket items like to renovate a bathroom, renovate a kitchen, replace the furnace, replace the roof, etc.
All wholesale deals should have free and clear title and you should be able to see the sales agreement before submitting the earnest money deposit. You should also have access inside the house in most cases. If the home is occupied, there's usually 1 group showing scheduled, so you'll want to come prepared with your comps and ARV.
When you go inside, you're verifying that the condition and estimated rehab costs match your expectations. There usually aren't photos of the basements and that's were most of the big ticket issues are. Check for cracks in the foundation, condition of the mechanicals, any water coming into the basement, etc.