For instance I did a job last summer actually repairing someone else's shit work. We had a land hurricane here 2 years ago and it tore this guy's rail off his deck, the stairs were separated and never attached to begin with, it needed posts underneath because of unsupported spans, a couple basement windows, etc. I broke it down with deck first including attaching stair unit, then rail which was some hollow composition crap which they had already bought and actually over bought since over half the original was still good, and then windows. Each is a different skill set and they had already blown money on the losers who built the deck before the storm tore their shit work down. Out of a sympathy I did $400, $300, $200. They bought materials.

I have people who have people and sometimes ask if I will do the work because bigger companies can't either be trusted and mark up parts like 200-300%. If it's a bunch of different jobs I just break it down by specialty.