Kristen,
   I absolutely, 100% would not put up with cockroaches in any house with
ferrets for the simple reason that the fuzzies will catch and eat them.
There's not much you can realistically do to stop them.
   I don't know about the bomb stuff effecting ferrets through the
carpet, so I can't comment on that.  BUT, after your landlord calls (and
pays for) the exterminator, if you still have problems, call the city's
Health Department and complain about the restaurant.  They'll either have
to clean up what's causing the problem or close.
[Posted in FML issue 0974]