2002 GMC Sierra Ignition function

We are considering purchasing 2002 GMC Sierra 2500HD.

Initially found ignition intermittently sticking, not turning to start regardless of steering wheel position.

Dealer has "fixed" 3 times with last report being replaced ignition.

We now find that ignition starts smooth as baby's rear, but find it hard to get the key OUT of the ignition.

Estimated cost to repair ingition so it performs properly? Considering skipping on this purchase completely as dealer doesn't seem to be able to get this right.