If you look for a used machine, you can get a good long arm APQS brand on a 10-12 ft frame for about $3000. Check a couple different sites for some prices.
Forum.apqs.com
Longarmuniversity.com
Houseofhansen.com
You can also check craigslist. Personally, I would be frustrated with a 9 inch throat, trying to do long arm quilting. Good luck!