The company I work for, does mostly new construction commercial projects. Concrete cutting/boring, pole bases, bollard bases, fire alarm, low voltage wiring, and ceiling wires for our fixtures are always excluded in our default contracts. We will sometimes do low voltage, but not by default.
We supply all lamps and fixtures, unless there is a note on the plans about a specialty fixture the owner will supply.
Change orders are a bigger deal in commercial construction. On big projects we are not allowed to issue a change order, we actually send out a Change Order Request (COR). The COR is sent to the GC, then to the engineers and then to the architect and finally to the owner. If the owner approves the COR, an approved change order is sent back down the chain.
This may seem overly complicated, but it makes sure everyone is in the loop on changes. This process even happens if the owner in person asks for the change order. I'll still write it up and wait for an approved change order to come back before proceeding. Generals love to push you to do work before getting approval back, but that’s the only guarantee you will get paid for it.
One other problem with commercial are the draws, usually you will be floating one to two months worth of work before you get paid. On a large job that can be a sizable amount of labor/material you are financing.
With the crew you currently have, I would actually recommend commercial service calls. You would need a large ramp up in tools, capital, and manpower for a decent size commercial project. This considering the profit margin is often quite tight on new commercial. The profit margin is substantially higher for service call type work.
Think of it this way, on a 10 million dollar project the owner will know what they are doing. They will know exactly how much they can squeeze out of you. While the secretary will not know that the $250 copier repair could actually be done by someone for $210.
I'm not trying to get you down, just trying to help you see what my company has learned over the years. Such that we are trying to get back into a more service call type company, with a few smaller new construction projects to help balance things out.
