When you select PayPal Business as the payment option on your invoice, your customers will be required to log in to a US-PayPal to make the payment for the invoice i.e. their country must be set to United States in their PayPal account.
Even though you have a PayPal Business account, you can select PayPal Standard as the payment option on the invoice creation page and your customers will be able to make payments using their credit cards.
Books
MTD ready accounting
software for small
businesses.