Upgrading to a performance brake kit with drilled rotors changes how the car bites on every corner. It is a satisfying fix, but running performance parts usually means paying a bit more for pads and dealing with more dust on your wheels. The best time to buy is late autumn or around major holiday sales when shops drop prices to clear inventory.
Financing helps spread out the cost, but keep your negotiations separate from how you pay. Lock in the best price on the hardware first before you ever mention monthly payments or credit.
The 0% intro window is a strict deadline, not free money. If you still have a balance left when those 18 months are up, standard interest kicks in on the remaining amount.