I have a villager in boxes today and I really don't want to get one through street pass. If I turn off spot pass it should prevent random move ins from other towns right? Thanks!
I'm pretty sure you just have to turn off the wireless button (on the right side of your 3ds) and it stops all connection (i.e. internet, streetpass, spotpass)
I hope this helps!
EDIT: This doesn't stop random villagers from out of nowhere to appear though. (like the ones that first moved into your town when you first played.)