If you have a credit card with a high enough limit to buy a hot tub, you can use it. You might also be able to apply for a credit card with bad credit and then use it for the hot tub financing. However, credit cards often have higher APR and higher interest rates than personal loans. Always use your credit card wisely and try not to ever use too much of your credit limit as this can lower your credit score and make it harder to get additional financing options in the future.