1. He makes his contractors submit alternate plans rather than submit change orders -- that's harder for them than just asking for more money.
2. For every item that is added to the budget, he requires that something else must be taken out of the budget -- that's super-hard.
3. He tells his contractors that if they submit a change order, they won't get any more work from him, which forces them to reconsider asking for more money and instead to do some creative brainwork. On the other hand, he doesn’t make his repeat contractors competitively bid for their next job with him. This works when you are consistently doing lots of projects. Jeff tells his contractors that sometime they will make a lot of profit and sometimes they make less, but they keep consistently making money.