What Should Be Incentive Structure?

Dear All,
I need suggestions from your side to develope the incentive structure for my organisation. I have joined this company in last Octomber. We are having dealership business. Before december 07 there were no formal structure for the Incentive. I have develop that for our all branches.
I am giving some amount for per vehicle sold to the sales advisors. Now i want to restructure it and I also want that my back office staff should also get some motivation so please guide me to formulate the Incentive Structure for the same.
Thanking you,
Devansh

Incentive plan is to be implemented as per the need and guideline of the Organisation.

It is organization specific. So no one can brief you about the incentive plan of your organization

Decide the amount to be offer per unit sale. (Should be more then present offer).
Devide it into steps, do not offer the whole amount in initial level achievements.
Make offer attractive for later stages etc. Anouncement of achivement should be communicated to all & with special wishes to the acheivers. Speacial Acheivement should be awarded/rewarded in a gathering just think over & you yourself will be able to design a good effective system. With such points gathered approach colleageous for further suggestion this will make your system more acceptable.
Best Luck.