We are now with Paypal. After reviewing the costs, we find it to be more cost effective and were able to get the non-profit rate.
Please note that you do not need to have a paypal account to make an invoice payment. Just choose the Don't have a paypal account option.
Please note that on the paypal page it may say donation but just put in the amount owing on the invoice. You can put the invoice number under more information at the end of the transaction.