Bad alignment

A friend of mine keeps getting a flat tires in the rear. Whenever new tires are put on they rub and the tires blow out. What is causing the alignment and tires to be slanted to rub? It is a 97 Civic. Was told it could be the Camber Kit but i have read that it isnt always needed to fix the Camber kit. The tires are slanted in at the top and out on the bottom. I am trying to help a friend out getting this repaired for cheap so if I could do the repair myself I will. Any advice?