C.O.
One of my friends via Facebook lives in Michigan and is in HVAC - he LOVES it...he just got promoted... I would talk to a few of the companies around your area and see what they are in the need for in HVAC - there are many different things one can do...like the poster below is looking for refrigerant...
he could be more successful if he gets certified in a field that appears to be in high demand!
GOOD LUCK!