What are the various stages of buying decision process?

I believe it has three stages:. A- before buying Here customers try to find what satisfied their needs and search for information about what they found. B- buying decision Here, customers compare between social and financial risks to make the decision C- after buying Here, if customers happy then they will buy again and if not then they will take actions such as informing others about their bad experience with the company etc.

Five stages

1. problem recognition

2. Information Collect / search

3. avaiablity alternative evaluate

4. decision of purchase

5. post behavir purchase