I looked at Craigslist and found Juki TL-98E's listed at $250 and $550. A Viking MegaQuilter on a Grace frame was listed for $1050. These are asking prices, not necessarily the prices they will sell at.
What are you hoping to do with the machine and frame you buy? The TL-98E is a domestic machine with a 9" throat. It has a good reputation as a piecing machine, but it is not a longarm (they have at least 18" throat) and its use on any frame will be limited. I have no personal experience with either this machine or the Grace frame. I have had friends who loved their Juki's, for piecing. I have read reports of people either loving or hating the Grace frame. But if money is tight, and you haven't had a chance to sew with this machine/frame combination, then I wouldn't recommend jumping in and buying it.