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No matter how well you follow the previous eight pieces of advice, you're never going to be as savvy as an expert, and it's often possible to enlist pros who really know what they're doing. "If you're buying anything, drag in somebody else," says Dowling. "Quite often you'll find an art expert or antique dealer will accompany you. Sometimes he'll [charge] a small fee" – Dowling suggests $250 wouldn't be unreasonable – "but he [might] actually get you a discount on the item you're about to buy." And it never hurts to pick up the phone. Dowling suggests calling other dealers to see what they have to say. "If you phone 10 people and ask them their opinion, two or three are just going to be horrible and say 'I wouldn't buy from him.' But if nine say that, then you probably know not to."