Some of the ways to reduce dissonance for a car include; after the purchase summarize the benefits of the car and house for the customers and also go over all the things or benefits that that the purchase will provide the customer. In case of the car you should provide after sales service and a toll free number so that the customers can communicate easily and remove doubts. For the car you can also offer refund policy for certain parts as well. The company should have a staff that can deal with customer complaints and for the house develop partnerships with insurance and maintenance companies and encourage customers to take advantage of services. Develop follow up programs and find out what problems the customers faced and then try not to repeat the mistakes.