I will never give a bite before payment. A "buyer" can just as easily scam a seller as it can the other way around.
The last time I sold my bite the buyer and I came to an agreement on the price. He showed up to the shrine and asked how to proceed. I suggested 50% up front with the rest after the bite was delivered.
That seems the fairest way to go about handling the bite trade. The seller is assured of at least something and the buyer can't skip off without paying at least part of the bill. While at the same time, if it is a scam sale the seller only gets away with half the going rate and possibly the bad rap to go with it (if the scammed buyer is vocal about it in chat).
I can understand the unwillingness to pay up front, but as a seller I am also unwilling to give the bite away before any payment at all. Both sides stand to lose big because the only thing controlling the transaction is the honor of both participants.
That said I sold a bite using the half up front system to a willing buyer and we both were true to the deal. He got his bite and I got the full amount we agreed upon and both of us were happy. Only wish more players out there were able to be trusted.
I don't have a bite up for around 3 more days though, so sorry OP I won't be able to sell you one anytime soon.
the problem here is that you can't complete the transaction at the same time, making it easily scammed. one has to do it first and it usually always end up one sided, /ignore and port away