Use an iTunes gift card to sign up for the developer program

I was in this situation once. However I went to the Apple support site, followed what they said, and then filled out the email form. From what I remember they will ask you for what you can make out of the code, and then the serial number of the gift card. This is the link to the email form submission page: http://www.apple.com/support/itunes/contact.html?form=cards_codes&topic=iTunes%20Cards%20and%20Codes&subtopic=Redemption%20questions Where it says 'specific request' select 'my code is scratched or unreadable.' Proceed to fill in the form as best you can and send it off. I got a response in less that 48 hours, and the answer they gave me allowed me to redeem my card. In answer to your original question, I don't actually know, but I hope this assistance means you will no longer have a need to refund the card. Hope this helps.

According to Apple's page, it uses the following order for song purchases:

• Song credits.
• Gift certificate, prepaid card, or allowance credits.
• Credit cards.

Thus, it would appear that you cannot charge a credit card without using up your credits or gift certificates first.

However, similar to what @Nick said, you could just open up another account, add the credit card to it, and then gift the items you want to your original account.

Update: Based on my own tests of self-gifting, these are my findings:

• Gifts will deduct money from the credit card on your account; they will not use up song credits nor gift card credit. This means that you do not need to open another account, just add it as a credit card and gift it to yourself.
• You cannot send a gift to the same email address as your iTunes account. This can easily be circumvented by sending it to one of your other email accounts.
• The easiest method of gifting to yourself is to select the print option. It will show you a code which you then use to redeem the song. It will allow you to redeem the code on the same account.