A reduction in interest rates could improve conditions in the housing market and lead to greater sales growth for Opendoor.Opendoor Technologies (OPEN -15.15%) has been one of the top-performing stocks on the market this year, rising by a staggering 500% thus far. Recently, it has taken a break from its high-powered rally and is showing signs that investors are perhaps growing a bit more cautious about its valuation, or simply cashing out some sizable profits.But if interest rates continue trending lower in ...