You want a drone that handles high-wind shots and stays stable for years, so aim for a model that won't feel obsolete in six months. Buying one that lasts saves you from needing an upgrade next summer.
Drone companies often drop new models in the spring, which makes the previous year’s version a smart buy. Wait for early summer retail sales to find those older models at a discount while they are still in stock.
The 18-month window is a deadline, not free money. If you have a balance left over when the 18 months end, you will start paying interest on the remaining amount at the standard rate.