A service upgrade involves more parties than most homeowners realize, and managing their expectations is half the job. You’ve got the AHJ (permit and inspection), the utility (meter pull, service drop, transformer capacity), and the customer - all on different timelines that may not line up. I’ve had service upgrades take two weeks and some that took three months because the utility was backed up or needed to run new conductors from the pole.
Your scope: new meter socket rated for 200A, new main panel or replacement of existing, upsizing of service entrance conductors (typically 2/0 aluminum or 4/0 aluminum for 200A), proper grounding electrode system, and all associated permits. The utility’s scope: verify transformer capacity, replace or upsize service drop conductors if needed, pull/re-set meter. Get the utility application in early - some utilities have a 4-6 week lead time just for the assessment.
Budget question everyone asks: materials for a 200A upgrade on a typical single-family run around $800-1500 depending on your market and whether the panel location moves. Labor is where you make your money - figure 8-16 hours depending on complexity. Quote it all upfront; change orders on service upgrades create unhappy customers.