I just used my foam cannon toady in the cool days of October here in Toronto. Extremely fun and everyone takes a second look in my neighborhood.
As long as you have the garage space for a pressure washer, the cannon, a couple of wash buckets, microfiber towels as well as any other sprays. (Wheel cleaner, glass cleaner, wax, polish, buffer, etc)
I didn't consider this first and ended up having to spend time/money on these things.
Plus it's a nice thing you learn over time. It's cheaper then going to a drive-through, safer if you're careful with what you're doing as well as some bonding time with your family if they choose to help out.
Hope this helps.