I was gifted a pretty gnarly looking blackstone this year. Rust top and bottom, although the top wasn't too bad. Vinegar soak and wire brush took care of most of the really bad spots. Got a couple of "toilet stones" from HD, they are nothing but glorified pumice stones. WAY cheaper than the ones branded by blackstone, two cost me $3 vs $10 for the single branded one. Rub the pumice stone over it with some vinegar/water solution and it will take those spots right off. Seasoned with avocado oil from Lidl. Get you a plumbers propane torch for the corners and heat underneath the griddle to season all the way out to the edge. Don't do it on top you will scorch the oil. I did 4 seasonings took me about an hour. Came out looking almost new on top.