Terms of Purchase Agreement. An APA is a legallybinding contract between a buyer and seller that finalizes the terms and conditions of an acquisition.This article offers guidance on helping clients take advantage selling personal goodwill as a tax strategy. Written custodial agreements are required to provide, among other things, that the collateral securities are held separate from the assets of the custodial. "Net Asset Amount" means the total assets included in the Acquired Assets minus the Assumed Liabilities of the Seller, determined in accordance with GAAP.