For $700 a month, San Francisco residents can rent a pod the size of a twin-sized bed ... housed inside a building with ...

The four-berth pods would be available to rent, primarily by those using boats ... which has recently been used for storage. It aims to use sustainable materials to build the pods.

Why it matters: Brownstone Shared Housing's founders say the pods, each the size of a twin bed and 4 feet tall, are an affordable option in a city that averages nearly $3,500 in monthly rent.