You would need to do 3 things:
(1) Share responsibility
Sale is not complete until the value delivered is measured and customer is satisfied (or delighted, if you will). As such, all post sale support activities are essential part of selling, since failure to create value and satisfaction can affect your repeat business as well as credibility with new customers. Sales support teams shall be treated as part of the sales group and shall share responsibility to ensure that the promised value is delivered & customer satisfied. You need to treat them as contributors to selling and make them accountable by asking them to interact with customers to measure value and satisfaction.
You can even ask customers for written testimonials, mentioning the name of sales and support staff involved, which will go a long way in maintaining their motivation to do a good job.
(2) Share rewards
Since the support team contributes to sales & revenues, it is only fair that they be compensated for creating value for customers. Once you ask them to measure value delivered, you can give them incentives proportionate to the amount of business and measure of value created. A part of the incentives kept for direct sales people shall be used for this purpose.
If support is something you will be charging separately, then support people are sales people already, who could command a part of the profit.
(3) Create accountability
You would perhaps need to make each sales person responsible for ensuring proper customer support, by co-ordinating with the support teams. It will be easier and effective to divide the support team into various groups and each sales person be supported with a particular support team always. This will also make compensations easier, make identification with sales people closer and create competitivenes between teams. But, in the final analysis, the sales person shall be the nodal agent for ensuring support success. This will force him to develop more rapport with support people & he can capture more value from them.
Some of the concepts mentioned, such as measuring value after it has been delivered, may be felt strange to you in your particular business, furnitures, but it can certainly be applied. It depends on the kind of furnishing you do, its customization and value capability.
Trust this helps.
23rd January 2007 From India , Delhi