Here is an example of you MAY be talking abput.
If ten sellers all try to sell the same new book: the one who sells it cheapest will be the first on the list, then comes the next one (a bot highrr in price) until you arrive at seller #10 who is trying to make the most profit and has the hughest price on the book.
Is that what you meant?
Your question is bit unclear about what you mean.
No, I don't buy from Amazon or ebay because I do not want to mess with a paypal account. The few things i order I look for certain websites to order from. If it is a SECURE site I use my credit card, others I have dealt with beofre I may send a check by registered mail. Don't buy much by mail, only what I absolutely need and can't get here.