My friends Simon (right) and David, flanking my friend Gwen, neighbors in Tucson. Gwen has been buying up inexpensive properties for years, fixing them up little by little, renting or living in them. Seen here, her latest acquisition, a geodesic dome out in the desert. With a diameter of 24 feet, it’s her latest challenge to carve out a living room, bedroom, kitchen, bathroom and sleeping loft for guests. But she’s up to it.