Except as provided in section 14, an art merchant, including an art merchant consignee, who violates this act by failing to provide required information or by supplying information which is false, mistaken, or erroneous, except for harmless error such as typographical error, is liable to the purchaser to whom the multiple was sold in an amount equal to the consideration paid by the purchaser, plus interest from the date of payment at the rate of 12% per year, compounded annually, upon return of the multiple in substantially the condition in which received by the purchaser.