Purchasing processes/ steps of buying cars...

This question is about the consumer purchase decision process. The five steps are:

1. Problem Recognition--perceiving a need
(a) Perceiving a difference between a person's ideal and actual situations big enough to trigger a decision.
(b) Can be as simple as noticing an empty milk carton or it can be activated by marketing efforts.

eg. a need to buy a car

2. Information Search--seeking value
The information search stage clarifies the options open to the consumer and may involve internal search and external search.

3. Alternative Evaluation--assessing value
The information search clarifies the problem for the consumer by
(1) Suggesting criteria to use for the purchase.
(2) Yielding brand names that might meet the criteria.
(3) Developing consumer value perception.

4. Purchase Decision--buying value
Three possibilities:
(a) From whom to buy: * which depends on such considerations
o Terms of sale
o Past experience buying from the seller
o Return policy.
(b) When to buy: * which can be influenced by
o store atmosphere
o time pressure
o a sale
o pleasantness of the shopping experience.
(c) Do not buy

5. Postpurchase Behavior--value in consumption or use
-After buying a product, the consumer compares it with expectations and is either satisfied or dissatisfied.

This website is quite useful. Take a look and it will give you idea how to write your essay.
http://www-rohan.sdsu.edu/~renglish/370/notes/chapt05/