I don't think vinegar does much, if you use a product like Nature's Miracle you have to treat it and let it dry before you wash it, otherwise you are getting the scent all over the sheet. How old is he? I kept a pee pad on a bench at the foot of the bed and Joey used that. If he's peeing in the crate, the crate is too big, or you don't take him out often enough. If he's not going on the carpet or floors he's doing great, and he maybe be going on your sheets because he smells a certain scent. This website has lots of great tips.
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