You can turn a wooden serving cart into a minibar by using Cambro wired shelving. The shelves are created for specific purposes, such as roll-down storage for cans of soft drinks, or wider shelves for tall bottles. You can create a space for a tub of ice, or even a container of sudsy water to emulate a wet bar. While not as portable as a folding cart, it can be stored when not in use or the shelving can be swapped out for other purposes.