Some sellers on eBay will accept payment methods other than credit cards. When you find something that you would like to buy, scroll down to the bottom of the page that it is on and there is a section called "Payment methods accepted". Many sellers will accept personal checks, money orders, and cashier's checks. Make sure that the particular seller for the particular item you want will accept something other than PayPal or a credit card before you bid! The only problem you may have with paying in this way is that if someone on eBay was being fraudulent it could be very difficult to get your money back. If anything looks sketchy either don't go for it, or try contacting the seller before bidding to clarify things. The Avon part of your question has already been answered very well. :)
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