Hmm.. Maybe you need a bigger washing drum for 7 people cloth. If I not mistaken Hitachi have a washing machine with a biggest drum but smaller size.

With such a big load, maybe you need a separate dryer instead combine type. Combine type cannot have full load for dryer. Example washing can max 12kg but dryer max is 7kg.

It double the cost of normal washing machine. Efficient is depend on how you use it. You cannot load max into dryer like washing machine. Otherwise some cloth will remain wet abit .