idk every flip this house has the flipper helping with demo. Lol.
But seriously,
Idk that it doesent just come down to dollars per hour savings, in truth it could be none if you had a hard dollar bid. But I 100% believe that it will help build repore' (not sure I spelled it right) with your contractors. You go from in Their eyes a big shot investor aka the man to somebody who will help them out, especially if it was hard money. You are improving their hourly rate.
It's also educational for you. It will help you see if you're getting taken advantage of by contractors, that being said, I always think it will be easier and quicker than it is lol. But that may help you walk on a deal because you see too thin of margins.
My answer would be if you have the time available, and want to build a team,then yes help out with anything you can. If you're too busy with other things, or don't want to or care to build a relationship with your subs, then dont.
I personally enjoy the work, I wish I had more time to do it. I help where I can but anymore, I'm basically just an expediter, and even then I drop the ball more than I should.