If you do vintage (70s and earlier), PSA 6 (EX-MT) is very affordable. It's above a PSA 5 (EX) which already means no creases by default, and if it were unslabbed how can you tell it from a PSA 7 (NM)? And if you go pre-war vintage, you can find some good deals on PSA 1s with back damage. You...