Happi, I say resi work makes the payroll but commercial work makes a profit. I run about 75+% resi. I have 34 houses going right now and 4 commercial jobs (a gas station/store, a strip mall, a steel fabrication shop and an office/warehouse for an underground utility company).
The commercial work brings in over TWICE the profit margin when compared to houses. I have tried to balance the two mainly because resi brings a steady flow of income through the books.
I track each job by manhours and materials to keep a close look at the bottom line. You would be shocked to see how thin the profit is on a house if you have to make a couple extra trips. And it's usually things you have no control over (like sheet rocker cover ups, AC guys ripping out a light or smoke detector to make room for the return air, or the lighting supplier sending an order that is missing half the items)
I suggest start small and cherry pick your commercial jobs. Then they will be calling you. Dont drop what you have now and go all commercial. It's a steep learning curve that can leave you broke on the "fast track".