Coker tire truing?

How often should one expect to have to have a tired trued on a Coker? I've had
mine about 6 months now and haven't really riden it all that much. It has spent
a lot of time on it's side in the trunk of my car. This week I noticed that the
tire is so out of true that it will actually rub the side of the frame at one
point in it's travel. At another point, it's almost perfectly in the middle, so
it's pretty far out.

How much should I expect to have to pay for this service from a decent
bike shop?

Thanks, Greg