Ignore Quantity. It is always fixed, since the BAHA website has no shopping cart.

In the Description field, enter the purpose of the payment (e.g., the name of the event and the number of tickets you wish to purchase, or the title[s] of the book[s] you wish to order). If you’re paying for a membership, indicate whether it’s new or a renewal. If you’re making a donation, we thank you.

Combine the ticket or book prices and enter the total amount in the Unit Price box. If you’re buying a book, add appropriate sales tax and shipping (see bookstore).

Click Update Totals.

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An automatic service charge will be added to each PayPal transaction.
It’s called a shipping charge but is, in fact, intended to cover PayPal’s service charge. Please do not deduct it from the amount you are paying.

PayPal Charge Scale

Transaction	Charge
$0.01–$50.00	6%
$50.01–$150.00	5%
$150.01–$300.00	4.5%
$300.01–$450.00	4%
$450.01 and up	0%