The number is cumulative, in that, with every transaction the number will go up or down. This does not necessarily mean that they have only been involved in 20 transactions or that they have all been positive, but rather this number is a cumulative score of 20. Buyers can click on this number to see how many positive vs. neutral vs. negative ratings the seller has accumulated as well as view the comments of users who have dealt with the seller. Buyers can rate Sellers from the Recent Purchases screen or the Post Feedback option in their Auction Manager. Sellers also have the option to rate buyers.
Sellers have the option of putting a reserve price on their auction listings.
A reserve price is the lowest price that the seller is willing to sell the item for. Sellers are not obligated to sell merchandise that has not met the reserve price. This amount is kept secret from the bidders until surpassed by a successful bid. Reserve prices are not popular with bidders and you would be advised to think carefully before using this option. A Yankee Auction is a form of multiple item auction.