Spectacular Cooktop And Oven In Same Cabinet

I assume you mean a 30 tall cabinet and not a wall cabinet.
Cooktop and oven in same cabinet. Cook tops and ovens are both commonly available from dozens of manufacturers in either 30 or 36 theres no reason to have them different widths. Undercabinet hoods attach to the underside of a cabinet above a cooktop or range. The cabinetry toe kicks are 4 12 and the base of the cabinet is just under 6 off floor so way too high and no amount of contractor modification is going to solve that.
A single wall ovens space needs are similar to a standard range and offer great flexibility of placement. A 30 wall oven should be installed in a 31 to 33 wide tall cabinet so that the sides of the oven are not too close to the sides of the cabinet. Building and installing a base oven cabinet with a cooktop above it.
Bosch says the oven should be sitting 4 34 off the floor to allow for clearance between countertop and also between cooktop. Building and installing a base oven cabinet with a cooktop above it. They are also called wall-mount hoods as they can attach to the wall instead of the cabinets.
The cabinet where the other range was located is probably special made for a slip in rangeoven. Its the double wall oven thats the space hogdouble ovens effectively remove 30 to 33 inches of usable countertop real estate. Please ensure that you review your product specs thoroughly before placing your order.
As for installing an oven in a base cabinet yuk. We also have covers that fit onto the front of your dishwasher so it can blend in too. Cabinets for built-in appliances.
Third you mentioned gas cooktop - whatever you do make sure you allow room for all the gas line connections. Most less expensive US cabinet lines only make a 33 wide oven cabinet so you arent even given the option to make a bad decision. For any range you will be bending for your food.