They often put little plastic plugs to blank off the screw holes on the "wrong" side. Look for the plugs and remove them. Take off a door (bottom hinge first is often best) - swap the hinges to the other side - swap handle over - rehang the door on the new side - replace the plugs where the original screws fitted.
Do same with other door. Make cup of tea.
Peccavi, November 2009