Anyone who has dealt with a shop can leave a rating and a comment. Reviews show publicly under the name given, and there are limits on how many can be posted in a short period to keep things honest.
We don't remove a review for being unflattering. We do remove ones that are abusive, name people who aren't party to the order, or are plainly fake — use the report link and an admin will look.
Shops on Spotlight can reply publicly, which is usually the better answer.
Didn't answer it?
Tell us what you're trying to do and we'll come back to you.