Sandy,
So glad you hired him! Your life will probably be a lot easier!
As part of his weekly goals, you may want him to report each week on a specific area he saved the company - a specific thing he completed that perhaps you would have subbed out before or a repair he made rather than a replacement, and the amount of money saved. Our site teams report an item of savings each week, which keeps them focused on expense control.
You may also want to set some long term preventive maintenance goals. For example, Scott who works on a late 70s/early 80s property cleaned all the inside and outside coils on 254 units over the winter, and has only had 4 A/C calls this season! It took him and his team's time each week, but think what they're saving on after hours calls, A/C repairs, etc.
Happy Memorial Day!