This is spot on and I'm pretty sure you have to have an FFL to do that for starters, legally of course. I have helped a friend do load development for his rifle and he just paid me back the actual cost of components that he used.
What I would consider doing for actual pay (profit) is taking the rifle from the friend and doing the full load development FOR him, and then giving him his rifle back with the load recipe that he can then take and use to make his own ammo. Price is hard to say ... if it's a good friend, you enjoy the process, and you have the time then do it for the cost of components plus a case of beer and call it good. If it's more like a friendly acquaintance then $100 plus components for what I described seems plenty fair.