ROME — As the fine art market rebounds from a two-year slump, investors should consider what happened when two established appraisers were called upon to place a value on Hole and Vessel II, an abstract sculpture by Anish Kapoor.

The artwork was made of polystyrene, cement and earth and stood about 3 feet tall. The appraisers were summoned after the sculpture was accidentally discarded by a warehouse employee in London and presumably destroyed.

A London gallery owner who had sold some of Kapoor’s pieces, rhapsodized over what he called its sensuous suggestion of a female body. He pegged its value at $904,000.

A co-owner of a London appraisal firm found the sculpture to be clumsy and absurd. He put its worth at only $390,000.

“(The gallery owner’s) views were colored by his personal likes and dislikes. (The co-owner of the appraisal firm), on the other hand, had no knowledge of the market for Kapoor’s works,” he wrote in his 2007 ruling.

The justice set the value at $578,000, based on the price of another Kapoor.

While the appraisers’ reach is broad, their valuations are influenced by everything from their personal tastes to the desire to make higher commissions, says Philip Hoffman, chief executive officer of the $100 million Fine Art Fund Group in London.

Appraisers who negotiate the artwork sales sometimes jack up valuations to boost their commissions. Auction house experts play a different game, giving lowball values in catalogs with the hope of bidding wars.

Appraisers also fudge valuations submitted to the Internal Revenue Service so clients pay less tax on inherited art and get bigger deductions on donated works. The IRS says that from 2006 through 2008, a majority of audited estate and gift tax appraisals understated the worth of the art by an average of 44 percent.

Michael Thomson-Glover, who worked for 27 years selling and valuing art at Sotheby’s in England and Italy, says appraisers have leeway in setting prices higher or lower without violating laws or professional ethics.

“When there’s a range of values, it’s perfectly reasonable to be conservative,” Thomson-Glover says. “We do a valuation for tax purposes, which is as low as the market will allow. Then, if we’re trying to sell it, we want to achieve a maximum value because we’re working on a percentage.”

Art buyers should know the motives of appraisers to avoid getting played, says Howard Rachofsky, a former partner at hedge fund Regal Asset Management.

When buying art, Rachofsky hires his own appraisers and pays them a set fee to provide a reality check on valuations from dealers.

“Dealers, if they have an artist they want to promote, they will give valuations that are higher than they should be,” he says. “That’s when you want to get an independent appraiser to say: ‘The dealer is telling me this. Where’s the market?’”