News roundup: New home sales rose to seven-year high in May … Study says home efficiency upgrades fall short, don’t pay off … Interest-only mortgages are coming back, but with safety in mind

Springing up: Sales of new homes rose 2.2% in May from the month before to their highest level in seven years. New single-family homes were sold at a seasonally adjusted rate of 546,000 in the U.S. la…