Every black Friday is when you spend like $9 at Walmart so you can replace your old Tupperware with new Tupperware.
Also, roombas can usually be had for cheap. Roomba had the patent for two brush rollers (not some brushes. Rollers) and having dual allowed roomba to clean a lot better than any other bots while not needing a bunch of suction power or other pricey stuff. About a year ago their patent time finally ran out. There’s been a couple other bots that have gotten dual rollers since then, but right now it’s mostly still roomba, so that’s what I recommend if you want to spend under $300 and have a Bot that picks up well. Replacement parts for roombas are also plentiful and often pretty cheap.