Another option you can use for feedback if you're the buyer (or seller responding to a wanted ad): at the bottom left of the first post of a classifieds thread there is a green button labeled "rate seller". Clicking this will auto-populate the link to the deal thread in the feedback form. This button is only on the first post of the thread, though, so it only works if the person you dealt with started the thread. Personally, I subscribe to any FS thread I
buy from, this way I can easily find it again to leave feedback
Oh, and the like button is not available in the classifieds, just in case you were in that forum when you couldn't find it ;-) Tapatalk ignores the settings of that forum and can still "like" posts in the classifieds, but otherwise the feature is disabled there