Note: I am a spammer. I was banned by CCN Steve who also deleted my original message and replaced it with this note. Please heed Hedwig's excellent warning regarding people like me (below). Thank you.
Why don't you just join the Army? They have free room and board, and you can spend all your pay on anything you want.
I DID do the math. $24.31 on $300 is a little over 8%. But that's for 10 DAYS!!! You think a credit card is bad? You just paid an annual percentage rate of over 243%. More than 10 times that 21% that seems so high on your credit card. If you had been able to put the $300 on a credit card and pay it in ten days you would probably have paid no interest. If you had paid 21% for 10 days the interest would have been about $2.10.