I think a Murphy bed will make this room look like wall to wall cabinetry. I'd advise removing the floating portion of the desk system and putting a high quality sofa bed on that white wall as you come in the door. The guitar can hang on the wall or sit on a stand between the window and the single bookcase. You may be able to replace the folding table in the master with a reworked version of that return that you remove in the office.

For the existing home office, I agree with decoenthusiaste. I think you would be better off taking away the peninsula portion of the office to open up the space. You are using the space for many functions, the space needs to accommodate the other uses. You can put a Murphy Bed or a sleeper sofa on the wall that has the peninsula. (I like the sleeper sofa ;) You can add doors to the built-ins opposite for storage for a cleaner look and be able to hide items. I would also add deep shelves to the wall right of the cabinet with glass doors for storage of items. I would do three shelves spaced far enough apart for large items.

I would need more information and pictures of the 2nd office space to make any comments.

Good Luck!!

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