LET'S MAKE A DEAL! Klimt's "Portrait of Adele Bloch-Bauer I." Even billionaire cosmetics heir Ron Lauder needed a loan to buy the world's priciest painting. In June, the renowned collector paid a reported $135 million for Gustav Klimt's "Portrait of Adele Bloch-Bauer I." Art world sources say Christie's helped finance the acquisition (slated for Lauder's Neue Galerie museum in Manhattan) in exchange for a promise from Lauder to unload several coveted Egon Schiele paintings from his private collection at the auction houses's November 8 sale. In addition to its standard 20 percent commission, Christie's is said to have factored in the priceless PR the sales are sure to garner.