Driving a convertible with the top down is one of those simple pleasures that makes keeping an older car on the road totally worth it. But when the fabric starts wearing thin and the plastic window goes cloudy, you are looking at a real repair bill before road trip season hits. Spring is when every shop gets busy, so shopping around for the part before the rush is your best move.
Separating the cost of the hardware from the financing is the smartest way to handle this. You want to negotiate the best price on the top itself and any installation labor before you ever talk about how you are going to pay for it.
Keep in mind that 0% intro APR for 15 months on purchases and balance transfers is a deadline, not free money. If you still have a balance left when those 15 months are up, interest charges will kick in on whatever is left over.