Tall cabinets will take some planning on your side. You will need the appliance(s) specs handy. Use a base oven cabinet and give it a ‘solid top’, then add the desired upper cabinets on top, whether it’s an open upper for a microwave, or just an upper cabinet with a door. You might also want to add ovens above each other. Design oven openings and order an aditional carcass material panel to be used as a fixed shelf.