Tiger, residential can drag you down in little details, and burn money in the process. Most resi jobs seem like 5 trades with 2 guys each tripping all over eachother all day.
Commercial, in my opinion is a lot more meaner, cleaner and leaner. Whether its new, or TI's, you'll find that most GC's who stay in commercial are more organized. And for the most part, more efficiant. And it will be more about "Contracting" the work, rather than the "relationship" with the end customer you need to foster in resi.
As for core sawing, demo, and patch/paint. Just go ahead and permentley etch it into every contract as an exclusion. Too much liability. Many GC's use these items as changes to hit the customer with as the job goes on. Just make sure you're covered on paper that some "will be required TBD on-site". Go over what you think you might need with your bid, and they'll add it to thiers.
You will need to find the labor for the jobs though, get a fast track contract and not perform on schedule and you could be doing it for free. And you'll never be called back again. Relationships in commercial are built on performance, and speed.
