(RECAP: One of the biggest barriers to a robust recovery in the housing market is a lack of supply. There are simply not enough homes listed for sale to meet the demand—and part of that is because a growing number of homebuyers are not selling their previous homes. It’s a strange new irony in housing. Lack of supply is driving prices higher, which is pricing some demand out and driving up rental demand. For others, however, the rise in home prices is providing useful equity to buy another home while still holding on to their old home, which is then providing lucrative rental income.)