Things like light switches (zwave, wifi) could probably remain. New owner would just pair them to their own hub/controller. Hubs probably go with previous own

Things like light switches (zwave, wifi) could probably remain. New owner would just pair them to their own hub/controller. Hubs probably go with previous owner. Turn-over too complicated - just unplug it and take it. Something like a Nest (or anything else with direct cloud integration) is a bit more complicated. You'd either have to unpair it from your account or replace it with a dumb thermostat.