I guess I should have said,,,,,,any used grills I buy gets a good cleaning down to brand new condition. Who knows what they cooked in them, rat, horse meat, etc. After that, i don't worry about the vent or the lid and bowl unless it starts flaking off. If that happens, I take my wire brush and clean off the loose stuff, scrape the bowl out with a plastic putty knife and cook on. Foil under the offset side save a lot of clean up. The top vent is a badge of honor like said