A solid video doorbell saves you from monthly cloud storage fees by keeping recordings local on a built-in drive or memory card. Aim for a device built to last at least five years so you aren't stuck replacing it every season.
Tech companies refresh these models constantly, which is great for you. Keep an eye out for last year's top-rated version during major sales events like Black Friday or Prime Day; you get the same performance for significantly less money.
Remember that the 18-month window is a hard deadline. If you have a balance left over when the time is up, the bank will start charging interest on the remaining amount at their standard rate.