“Auction houses are popular stops for aficionados, since they do all the quality control on their behalf – Christie’s averages two movie poster auctions a year in London. Its most recent was in March, where a poster for the 1954 Humphrey Bogart/Audrey Hepburn film Sabrina netted $15,480 (U.S.). Experts had expected it to go for between $4,000 and $7,000.”