If you go to the Northern Usambaras, stay in either Mambo Viewpoint Ecolodge or the adjacent cheapy sister Mambo Cliff Inn, both situated on a cliff at an altitude of 1,900m on the outskirts of Mambo village.
Mambo Viewpoint Ecolodge is owned and managed by a deeply environmentally & socially committed Dutch couple. They are a great source of advice as to activities on offer in the region. Accommodation is in the range of spacious stone cottages, en suite safari tents or camping. Food is eaten communally, so that has to be your thing. Prices are around US$ 110 for the cottage and US$ 85 for the safari tent per double, bed & breakfast