There are two main styles of auction: a timed system and a hammer system. A timed system has an auction listing end at a specified, fixed time. They are also usually proxy bidding systems. The highest bid placed before the auction ends, wins one bidding increment over the next highest bidder. Examples of timed systems include eBay, ComicLink, and Catawiki. Timed systems are synonymous with sniping. As such, most of the bidding action happens in the last 60, 30, or even 10 seconds! A hammer system is a more traditional auction. There may be a pre-bidding session in the weeks before, but the auction has a start time where the lots are opened for live bidding and then sold one after the other. Live bids could come in via phone, internet, or in person by bidders "in the room". Examples of hammer systems include Heritage, Christie's, and Sotheby's. A hammer-style auction does not necessarily have a real auctioneer; rather, it could be entirely automated (such as with Heritage's weekly Monday auctions.) Automated or moderated, most of the bidding action takes place during the live auction period. There are hybrid systems which combine elements of the two systems, such as Hake's or ComicConnect. These auction listings start with a fixed ending, but guard against sniping by extending the ending as long as there is still active bidding in progress (see Time extension). Pros and cons: Hammer systems maximize results for the auction house and the consignor. However, due to their cost and complexity, those houses typically charge higher fees of 15-40%. Timed systems can be fully-automated and keep costs down for the house. Those houses typically charge 10% of the final bid in fees. Hybrid systems try to maximize results while still being fully-automated. However, many collectors find the seeming endless extensions of the active bidding to be inconvenient. Buyers bidding in multiple listings in one auction usually have difficulty juggling the ending of each one as they become moving targets. Auctions sometimes have reserves. A reserve price is a minimum price to bid to win an item. eBay reserves are hidden. Whereas, Heritage and ComicLink will open a piece for pre-bidding, but automatically raise the bid one step below the reserve a few days before the end of the auction. European auction houses usually start bidding slightly below the lower end of the estimate. See Reserve price. Auctions are notorious for charging numerous costs on top of your high bid. You MUST budget for these ahead of time. Other costs include: buyer's premium, wire transfer fee, credit card fee, shipping, resale right, customs fee, sales tax, storage fee, late payment fee, etc. Please review all terms and conditions well before the start of the auction. Christie's Cost calculator: buyer's fees would sum up to 49.5% (shipping within the same country) if lot sold at low estimate (and the seller would probably get 57% of what the buyer would pay, with a seller's commission of 15%). With the exception of eBay, most auction houses will send an invoice to be paid in the week following a major auction. Depending on their terms, payment is usually expected within 7-30 days. Different houses accept different forms of payment. Again, always check the terms before the auction. Don't expect every house to accept a credit card, PayPay, cash, or a personal check. Some smaller or regional houses may not handle shipping. Be prepared to contact a third-party shipper near the auction house who will charge you a fee to collect the art, pack, and ship it to you. This is common when dealing with houses listed on Invaluable or LiveAuctioneers. See: Comic art auction houses (comparison table)