I would level the cabinets and countertops; with the investment you are making you want a quality professional job. You can always get a window squeegee to get rid of any standing water but I don't think that you will have much/any to worry about.
Weber 26.75 OTG w/CI grates & SJ/WSM Mini
Home built 24"x72" reverse flow stick burner trailer with 18"x44" grill w/CI grates and upright SS gas oven/smoker.
Home built 48" fire pit with a 30"x30" Santa Maria style ranch grill.
Home built lump charcoal retort, iGrill & a bunch of other cooking toys.