Welcome to Amazon Services Business Solutions, a suite of optional services for sellers, including: Amazon Selling, Fulfillment by Amazon, Amazon Advertising, Transaction Processing Services, and the Channel Partner API. The seller must provide the buyer with a receipt for cash transactions. For certain sales contracts, i.e. those concluded in a place that is not the permanent seat of the seller, the buyer has the legal right to revoke the contract before midnight of the third working day following the sale. For more information on this “cooling-off period,” see the laws of your state and the Federal Trade Commission. When communicating with us by e-mail, the seller agrees to receive communications about electronic records.