I am selling my kindle and getting a paperwhite. I need to clear it of all my account details, how do i do that? and will my books stay in my amazon account to reinstate on the new one?
You need to sign out of your Kindle, and on receiving your Paperwhite you sign in using your Amazon id and password to download all that's in your library.
If you fail to deregister, you can delete any books, but the remaining books and any future books you purchase will be available to the person who buys your Kindle. Do you really want that?
I don't know much about Amazon or kindle however I think leaving (if even possible) books on there would be in breach of Amazon policy. You'd be sharing a book(s) without permission.
the books are linked to your amazon account, not the device you are reading them on therefore if you want to leave books on it, you will have to leave it connected to your account