This is probably a dumb question, however how do I go about sending an invoice to a client which doesn't ask them to create a new paypal username and password? I just want them to be able to only enter thier billing info, and thats it.

Don't get me wrong, I've created many paypal invoices, but everytime I create one and send it to a client, they are always asked to create a new paypal account. I don't see how to get around this, what the heck am I missing?

Thanks for any input!

If you need the invoice to support Account Optional, you must send the invoice from a Business or Premier account, and it must be sent to an email address that is not already registered to a PayPal account.

If you're doing that, and the customer still does not have the option to pay with a credit card without signing up, you might need to send them a URL for a Website Payment instead. You can still assign an invoice number if needed.

For a single item, you could do something like this:
https://www.paypal.com/webscr?cmd=_xclick&business=YOUR_EMAIL_HERE&item_name=Invoice&invoice=12345&amount=1

For multiple items:
https://www.paypal.com/webscr?cmd=_cart&upload=1&business=YOUR_EMAIL_HERE&&invoice=12345&item_name_1=Item1&amount_1=1&item_name_2=Item2&amount_2=1

In the examples above, you need to insert the email address that's registered to your PayPal account as the "business" value, so that the payment will be directed to your account.