just don't leave anything out in the open. make sure they have easy access to the furnace in case they're changing filters. (they always did this at my inspections) try and not look like a total slob and you'll be fine. i never disposed of guns, drugs, etc. for a silly little inspection....just put them in your underwear drawer....and empty/wrap up the bongs.
they're probably just checking smoke detectors, furnace filters, and making sure you haven't completely fuckered the place to all hell....aka holes in the walls, etc.