Buying a raincoat means you want to protect yourself from emotional harm, or you want to be more independent.
Dreaming that raincoats are colorful, I chose my favorite color: choosing my favorite color means that my mind will change, and if the color is bright, it means that I will become more optimistic.
Your dream may also be related to the real raincoat.
Generally speaking, this dream indicates that the dreamer will become more independent and know how to protect himself.
Your background is the key to dream interpretation. Good luck!