Danielle and Frank Sheahan turn a short, squatty lighthouse in Wales into a fun eclectic six-bedroom home. Magali Mayorga Rivas and Fernando Becker live with their young family in a unique underground home in Mexico, where the garden is on the roof of their house. Teun Van Wely's home is just 8-feet wide, and the Amsterdam house comes complete with a mythical story of its creation.