I would suggest buying one that hooks up directly to your computer. Other wise the money you save on the machine, can be upped by the additional equipment needed for the designs.
Singers around the $600 amount hook up to the computer, but they don't have hoops as large as some of the other more expensive machines.
If you are wanting very large hoop sizes, then you may want to look into gently used machines.
Get in writing from the dealer though that the machine will still be under warranty. Not all warranties may be transferable. :D:D:D