You know, maybe you could look at this another way. If you get an instructor from your local club you won't need to crash your trainer at all. Mine was perfect until I decided I could train my dad after a couple of months of flying, (MUCH harder than I thought!), and even that was fairly minor damage. If you insist on cheap and crashable you might want to check out www.spadtothebone.com and look at their free plans. Close to what you're looking at.
Tom