Asking currently listed properties if they will sell after the property has expired

[Keith Belzner]

Hi Bp,

Just wondering if you can ask a seller of a currently MLS listed house if they fail to sell and it becomes an expired listing to give me a call? Is it legal? How about a yellow letter or post card saying to some effect, " i see your selling your house, if are not able to get your price give me a call........"