I think I may need to be buying a new wall oven/microwave combo. The repair quotes I keep getting on my Jenn Air (previous owner of the house put this in) are getting to the point where may be better off getting something new. Wife and I don't love it anyway

What brands does the board recommend and recommend to avoid? Not looking to go crazy expensive top of the line here since we likely will be selling the house and moving in 2-3 years.

The biggest issue you will face is finding a unit the same size as your old oven/microwave unit. Otherwise, you will have to redo the cabinet openings.

Yeah I'm concerned about that

If its non-op, yank it out and measure the opening. As well as how much space is available if it does need to be expanded.

Then see what your options are.