Payment is due within 3 days of sale. PayPal only. I will be happy to combine items (if weight allows) if you pay for the items at the same time. Please note that I cannot ship books with other non-book sales with Media Mail Rates. In that situation, combined shipping would be USPS Parcel Post. I strive to ship within 2-3 days of payment. In order to offer the lowest possible shipping costs, I will adjust shipping based on location at the end of the sale on the invoice. I WILL NOT exceed the original shipping quote. New York State Residents will be charged sales tax. 100% refund however I do require the item to be returned no matter the condition it was received.