A demo means demonstration in this context; basically you’ll get a new model mower from a local service dealer, usually directly from the manufacturer via one of their sales reps, to use for a few days to see how you like it, with the idea of you’re serious about purchasing one. It used to be a relatively simple thing to do but since Covid it was a lot harder with supply chain issues and what not, 2021-2022 there were no demo units available at all. This year, I was finally able to get my hands on the vertex.
