There is a homebuying myth that needs dispelling. It has to do with mathematic certainty. The truth is, no formula exists for knowing if and when you should buy a home. Ask most economists and they'll tell you that there are far too many emotional factors involved.
Every entrepreneur thinks they are designing for a complex and dynamic system. In the case of the housing industry, though, there really is very little one can take for granted, especially when designing for Millennials.