I recently bought a used Voyager 17 with Hinterberg stretch frame (plus some extras) for $3,000 from a fellow quilt guild member. This is a nice beginner setup. Someone else on the QB recently purchased a similar setup near Chicago for $2,200 and hers even included the stitch regulator. The Voyager is really a midarm rather than a longarm, but it's at the larger end of a midarm. I am loving mine so far.
Edit: The quilter who sold me my setup had had it for 7 years. She sold it to upgrade to a used APQS longarm for about $7,500.