I have older cabinets, but I have bought a new electric range and a new microwave oven/hood combo. The problem is the taller head on the new range and the larger size of the new microwave is combining to make the microwave sit right on top of oven, not good. The microwave is attached to the bottom of one of my cabinets over the oven. The cabinet is currently a 30x30"" framed, oak cabinet, with two doors. I figure I need to trim at least 6 inches off the bottom of cabinet to raise up the microwave for safe and practical use of both the oven and microwave. Is it possible to shorten the cabinet and re-install the floor of the cabinet so I could still install the microwave on the bottom of it? Dont want to buy a whole new cabinet because I am afraid it will not match rest of cabinets. I have received opposing opinions on this from friends. One says it can be done by an experienced carpenter, another said no it cannot be.
Sounds like you just need someone to switch that cabinet to a 24"x 30" unit, instead of the 30" square one you have. Depending on your door style, this isn't too hard. They could possibly use the same doors, hinges, hardware, and just make a new cabinet box to fit into that space. Like I said, it really depends on the kind of doors you have in that unit.
Yes, an experienced carpenter can totally do that job. If they're just taking the old one out and putting a new box in, that would probably be a full day job, since they'll probably install the microwave vent fan up through that unit. Then reworking the doors - if that's possible - would be another day, roughly. I'm guessing that it's a two day job, minimum, and you can price that accordingly.
This is a pretty difficult job for the average homeowner to tackle, I pretty much recommend against it, unless you have access to a decent arsenal of tools, and have some skills, too. Cutting the cabinet loose and removing it is a chore in itself, and you don't want to get into the middle of it and get stuck.
Tell you what - if you want to send me a picture of the cabinet through this site, you can do that, and I'll have a little better idea of the level of difficulty. But right now, I'd advise against tackling it yourselves. Call in a professional.