K.M.
I bought a Hanes brand body shaper that is very similar to Spanx, but much less expensive. I found it at the Leggs Hanes Bali outlet store. They had several styles to try on.
The one I got doesn't allow for any "spillover", it just makes me look about 2 dress sizes smaller and much flatter and firmer. It comes up to just under my bra line and down to my thighs, but not very far down. And there's no "poofing out" where it ends.
If the Hanes one isn't an option, try Spanx. You'll be amazed.