There is a custom module in Drupal 9, for a car auction.
There is a minimum bid ( reserve). There is a minimum elevation for the next bid. Every new bid is safed in the database.
The bids are working with comments types. So you should see this as working with the comment types.
All work fines, but follow need. When a user delete his bid, it should also be deleted in the DB. The previous bid, if there is one should be then the last bid. Or if no bid before the reserve price should be put in the DB.
Second part is render the last bid as a placeholder in the integer field.
site www.2dehandsauto.be Project in Gitlab. No CSS, only code.