I had 5 walls done in our 19 . It includes both sides of the frig, both sides of the bath and kitchen. That way I can easily put shelves in the wardrobe and micro cabinet. They only reinforce to about furnace level. The frt bath wall already has a brace installed for hooks.
Dave I'm having trouble visualizing -- when you say both sides of the frig, do you mean the wall that is flush with the bed and the wardrobe door? And both sides of the kitchen -- does that mean the wall on top of the bench seats? I can't figure out which is the bathroom wall would get reinforced.
There are 2 sides to the frig and bath. The outside wall for the frig is the bed side the inside wall is the wardrobe. Same with the bath. The outside wall is in the frt dinette, the inside is the other side of the wardrobe. The kitchen is just one wall bedside. Hope this helps. Reace can explain it if you are interested in doing it. I choose to do them all to allow any mods I may want to to the the wardrobe, or microwave cabinet.