If you got all your money back you are lucky. Next time don't bid on something on ebay until you are sure you know what you are buying and have your questions answered. Secondly and more importantly don't sign a contract especially one with a non refundable down payment without knowing the specifics and are sure that you want it. The time to do research and price comparison is before signing not after. As mentioned by several posters, rescision laws for the most part apply to purchases from the developer not private resales and although bidding on ebay is not binding for real estate, signing a contract with a seller is a legally binding contract. Just opening a cc or paypal dispute may get your money back for the short term but if the seller can still hold up his end of the contract he can still sue you for breach.
If you want a timeshare take your time and research first.