Thursday afternoon, about 50 seniors, homeless and other community members participated in the Sacramento Housing Alliance Affordable Housing Bus Tour. The tour surveyed 10 different housing options and stopped to provide in-depth tours of three housing complexes. Guided by Shamus Roller, director of the SHA, Ken Cross, CEO of Sacramento Habitat for Humanity and Paul Ainger, Mercy Housing project developer, the four-hour tour began and ended at the SHA office in Midtown. "It's important to know what affordable housing means," Ainger said. According to the federal government, housing is considered "affordable" when a person renting or buying it spends no more than 30 percent of his or her