Tiny HousePlan 52781 It measures 20 feet wide by 24 feet deep and has a surface area of square feet. This model has an open room which includes the kitchen, living room and access to a bathroom and a master bedroom.
Tiny elevator could make this work for a senior. Finish out one garage bay for storage and insulate the door, but leave it in case a second car is purchased. Barn home for a sloped lot. (Double door garage in basement area)