The idea is that pets generally provide emotional support for homeowners. I recently gave a paper that was co-authored with Tim Allen, professor and director of the real estate center at the College of Charleston, which found allowing pets in condos has a positive effect on condominium prices in the South Florida condo market.
http://www.kansascity.com/2010/07/01/2056350/real-estate-qa-pets-in-condos.html#ixzz0sXAPeEQp
