under sink water heater
My has rented a very small beauty shop for 15 years. It is connected to a house. Her electric is billed separately by the Utlility but her water (hot/cold) comes from a shared water heater in the ajoining basement. She was billed a flat amount from the landlord. Persoanlly I think she was paying way more water than she was using.
There is now a new owner. He wants to sever her tie to the main home's water heater. He wants to install some sort of little water heater or something in the cabinet under her hair sink and one in the bathroom. (Note there never was hot water in the bathroom so this could be nice I guess...though the bathroom is seldom used.
My question is, what are these water heater thingys, how do they work and by having them will she have hot water quickly or will she have to wait? Also, what is the added electricity cost of these...are they heating water all the time or just when called for etc?