Buying a Property with Exterior Asbestos Siding

Has anyone here ever bought a property with asbestos as the exterior siding material?  If so, what are the problems that might arise out of owning or purchasing a property with asbestos siding on the exterior?  (Exterior only...not interior.)  I am posing this question because I have seen a number of properties with asbestos siding, and am not sure if I should pass on these properties for that reason.  

Thanks in advance.

Hank