A car is a massive money sink, and the costs don't stop once you drive off the lot. Between fuel, insurance, and routine upkeep, keeping your ride comfortable eats up a good chunk of change. Spring is the sweet spot for getting work done, right before the summer heat spikes and shops get buried in bookings.
We need to talk about getting the price right before we talk about how to pay for it. Always negotiate the tint package on its own merit first, getting quotes from at least three local detail shops. Financing tools are just for spreading out the hit, not for covering up a bad deal on the install.
That 0% window is a deadline, not free money. If you still have a balance left on the Citi Simplicity® Credit Card when those 18 months run out, deferred interest will hit hard and wipe out any savings you made by timing the spring install.