user roles – Filter Post in front end by using author ID

Am working on a car parts year/make/model/product/engine lookup WordPress site, what I want to achieve here is create a form where you can select year/make/model/product/engine and then you add them to the database as a product post. I want only the customer who added the product to be able to view the product added and add it to cart. A default user details will be added for the user when the customer logs in it replaces the session login details.

I really need help on this.
Thank you.