Billions of dollars in mortgage servicing rights have changed hands over the past two years and the selling is far from over. The question now is how much more will be sold by the end of 2013. According to analysts who cover nonbank buyers of MSRs and other sources $1 trillion to $1.5 trillion in rights could transfer over the coming 18 to 24 months, though some of that is in the form of subservicing contracts. Over the next year the figure could be...