I don’t know how you feel about second hand robots, but they are dumb enough to respect your privacy. The old Irobot roombas, They just run off of a internal clock, no connection to the internet, they bump around a bit, then dock themselves when the battery starts to get low. I pick them up at flea markets for 20 bucks, usually need to replace the battery, brushes, but they sell all that. Be weary if they smell like poop.