Daniel Grant, 'Art Collectors Weigh Title Insurance. Protection Is Often Recommended, but Most Collectors Aren’t Buying It', Wall Street Journal, April 12, 2015
One quote for the premium for a painting or similar art piece is a one-time payment of 2-3% of the purchase price. It is not stated whether the amount and quality of the collecting history held affects that. I wonder though what the premium would be for antiquities bought no-questions-asked? But then if it's a case of 'they-can't-touch-you-for-it legitimacy', I guess it makes no difference what documentation there is, or is lacking.
When you buy a piece of art, can you be sure it’s really yours? Many collectors don’t always feel certain on that score. They worry in some cases that after they make a purchase someone will show up, maybe years later, and claim the art was stolen at some point in the past—ultimately leaving the new owner empty-handed, without the art or the money paid for it. That’s one reason many art advisers and lawyers recommend title insurance, which can at least partially protect a collector’s financial interests if a piece of art has to be surrendered. [...] some insurance companies offer “defense of title” coverage, which typically pays up to $100,000 in legal costs in the event of a title dispute but doesn’t reimburse policyholders for the value of any objects taken away from them.