I've recently conducted two transactions with the same seller, based on the same ad. I left feedback after the initial transaction because it went very well. A couple weeks later, he still had some items remaining and I bought them at that time. Is it possible to leave him a second feedback, given that they were separate transactions? If so, how do I go about doing so?
Sure, why not?! You had two separate transactions. All you need to do, I think, is post a second reply
in the thread for the items that you transacted on later. A Mod could chime in to validate that.
GoatBoy was forced to disable the multiple feedback ability because so many people were leaving multiple retaliatory negative feedback for each other in the same thread. Now it's limited to one per ad.
ETA: SiVisPacem, IM me if you want - I'll see what I cab do (but I might not be able to get to it tonight

).