I partly agree with Ted. Having replaced my microwave at home, they are easy to remove, It is only a couple of screws and sliding it off of a bracket. A little heavy/bulky, but easily done.
Where I might disagree a little bit is you said you will be replacing it with a different model. Chances are it come with a different bracket, requiring remounting changes. Depending on how handy you are, that might involve some work. Personally, I would not pay somebody to do it. (I am cheap!) I would do it myself.
If you search the existing microwave model number online, you can probably find the installation manual for it, and it will show the screws and type of bracket. And how to remove it, or at least how to install it so that you can work backwards.
'04 Alpine Coach 36' MDDS