There are so many possibilities that could go on here it will be very difficult. That's why my initial recommendation of accurate time sheets and remembering the whole quarter, or year, or what have you, for bonus dollars works best for me. At the end of the said period I can look back and see who worked the most efficently and if there were any customer callbacks with praise for a specific installer etc....just my 2 cents. Building a good relationship with your installers is very important, they are the front lines and can really make or break your company. More so than the salesmen.