Spring is the sweet spot for solar work. The install crew is coming out of a slow winter, you catch them before the summer backlog, and the panels hit their stride right as the long, sunny days kick in. Most homes get power within a day or two of finishing, so the change shows up on your next meter read rather than some far-off promise.
Solar quotes vary wildly, which is exactly why you want at least three of them before signing anything. One installer might spec a 6 kW system with premium black panels, another a 7.2 kW setup with standard hardware, and a third might just beat both because they're trying to fill a crew's slow week. Comparing apples to apples is hard here, so the more quotes the better.
The 0% intro is a deadline, not free money. If even a small slice of the $20,000 is still sitting on the card when month 18 closes, that leftover starts accumulating interest at the regular APR right away, and the rate is usually well into the double digits. The plan only works if the balance is fully cleared inside the window, so build the payoff date into your budget before you swipe.