With OxyClean I, like you, have found that you may need to repeat the process a couple of times, but it looks differently every time you treat it. Eventually.....All Gone!!!
I've also heard that you can save money on do-it-yourself reupholstering by buying fabric remnants. The store is trying to get rid of them, anyway....and bargain, bargain, bargain with the store manager or owner!!! Offer/Counteroffer!