There’s more than $2.1 billion of art for sale at the New York auctions next month. Almost half of it, including an Andy Warhol painting belonging to billionaire Steven A. Cohen, already has a buyer before the first paddle goes up.

When the two-week sales start Nov. 4, $1 billion worth of paintings and sculptures are guaranteed to sell by Sotheby’s, Christie’s and Phillips at minimum prices regardless of what happens in the salesroom. The companies are lining up deep- pocketed backers for the guarantees or financing them with their own money -- a risky proposition because they can end up owning the works if there are no takers.

“The question is not if the guaranteed work will sell,” said Thomas C. Danziger, managing partner at Danziger, Danziger & Muro LLP, who helped structure several guarantees for November. “The only question is at what price and to whom.”

The amount of guarantees has surpassed the pre-recession peak as auction houses battle for trophy artworks and market share, especially in modern and postwar art, the segments that command the highest prices. Sotheby’s is financing the biggest guarantee for a single collection in auction history: $500 million for the estate of its former chairman A. Alfred Taubman.

“The stakes are extremely high,” Kristine Koerber, a senior analyst at Barrington Research, said in an Oct. 20 report. “We have never seen this level of guarantees for one auction and/or a collection.”

Strategy Backfired

Popular during the previous art market bubble -- Sotheby’s guaranteed $902 million in 2007 and Christie’s guaranteed$800 million in 2008 -- the strategy of offering a minimum price to sellers to help land consignments backfired when prices plummeted during the financial crisis. Sotheby’s incurred $60.2 million in losses on guaranteed items in 2008, according to a filing.

As the art market roared back and competition heated up, guarantees again became a major tool to win top lots. There are 267 guaranteed lots in the November sales. Sotheby’s and Christie’s, which have been locked in a fierce battle over market share, each expects to sell at least $1 billion of art and has about $500 million backed by guarantees. Phillips, the smallest of the three houses, expects to sell at least $75.3 million, of which about $42.9 million has either in-house or third-party guarantees.

The November sales will be the biggest test of the art trade since the global stock market rout in August and September. Collectors and investors are looking at whether the auction houses will be able to match or surpass the record $2.7 billion sold during similar events in May in New York.

Guarantees have played a crucial role in the escalation of art prices, said dealers, advisers and auctioneers. In May, Christie’s guaranteed a painting by Jean Dubuffet, which fetched $24.8 million, more than three times the artist’s previous auction record of $7.4 million set only six months earlier. Another guaranteed lot was Pablo Picasso’s “Les Femme d’Alger (Version O)” which sold for $179.4 million, the record for any artwork at auction.