Make sure the machines can be hidden with cabinetry when not in use.

One thing about front loading washers (which at first glance seem easiest to hide in cabinetry): Most of them need to be left open to dry after a load has run. The gaskets are almost too good, and moisture gets trapped, with stinky results. The fact that the door has to be open for a while often gets in the way of any doors to hide it.

We have ours behind 2 bi fold doors in the kitchen. When in use I can open them to air out. Saved us a lot of space!