4% the 1st 12 months, 2% after that for the life of the account and his employment. Think about it, 4% is very close to the same ammount as a free cut in a 20 cut season when you factor in your share of FICA etc. You could adjust this percentage to match the cuts per season if offering a free referral cut. Most of us would gladly offer a current account a free cut for a quality referral. Also, spell out a comission reduction if the service contract is negotiated at less than the standard rate to meet or beat a competitor's quote. You cannot pay comission if the margin on the job is to low, also gives him incentive to keep prices up.
My wife said "you're on lawn toy restriction"