How can you tell if one of these lost works is worth buying?

In the meantime, keep these points in mind before you bid:

·                        Know your artist. If Rembrandt had a wacky phase, it has been documented elsewhere by credible authorities. If Modigliani signed his work in the upper front right hand corner, don't bid on something "he" signed on the lower left stretcher on the back. If any piece is already part of a museum's permanent collection (and a web search will tell you this quickly), chances are the "real thing" is still in the museum, not up for auction on eBay. Do your research.

·                        Know your terminology. Descriptive wordings such as "in the manner/style of", "after" or "attributed to" are all light years away from "BY". It is not uncommon to read an artist's name in an ad's main heading, only to have the seller write disclaimers throughout the rest of the copy.

·                        Know what a provenance is and demand to see it beforehand. It doesn't matter from which attic this lost treasure was unearthed, there must be documented proof that the piece went into said attic. If an ad promises to name names, dates and locations after the winning bid, avoid that auction like the plague. It is virtually screaming that the seller hasn't got a shred of proof of authenticity.

·                        Know what market values are. Again, this involves research. However, both ArtPrice and AskArt are two good starting points for finding this information. Each offers limited free data, with ala carte shopping for more detailed goods. Considering the final amounts on some of the auctions, paying for certified information before bidding is a good investment.

Finally, please remember that the old saw, "If it sounds too good to be true, it probably is", is an old saw because it is valid. If the piece up for auction is truly by Renoir, why aren't Christie's and Sotheby's in a pitched battle to sell it? Common sense is another valuable weapon in the anti-fraud arsenal of collectors. Use it, and don't get taken!