Home service businesses (contractors, electricians, plumbers, HVAC, roofers, etc). Even houses owned by banks/investment groups need repairs done. It's a huge industry that desperately needs employees.
These are among the first businesses to get hit by a recession. Sure, you may call the plumber to fix a leaky pipe but that bathroom remodel project is on hold. New construction, where a lot of contractors make the bulk of their money, also dries up.