Good advice here from everyone.
A 200A service with romex should not be a whole lot different than the typical residential job.
Each bid that you do will provide you with valuble feedback regardless of whether or not you win the bid. We don't always aim to be the low bid, but we do want to be competitive. That way we will get our share without losing our shirts. If you are low everytime and are "leaving alot on the table" you will soon be out of business.
GJ
