Enjoy the trip, I know you'll enjoy it.
First, have your budgetary needs firmly in place.
Then test drive a variety of machines within your budget.
Know the features you need vs want. Fancy stitches are fine, but will you really use them all? Need vs Want.
Which machine do you bond with the most. Which machine can you intuitively work with to your advantage. Which machine can you work with and have an interruption and yet still go back to sewing without any difficulties. Which machine can you visually work with the best. [I remember the old Bernina's with the knobs, I wouldn't have been able to select the correct stitch with my kids around!]
Check for financing if that appeals to you. Know you can pay it off early and most financing plans are no interest for quite a while.
See if you can make a deal on a show machine. They usually offer great deals.
Me: I have a Pfaff. It fits the way I think and work. I also know of a great machine repair person here in the Valley who I make an appointment with and get same day service!
Hope you can bring friends up with you for the Rusty Barn event. PM me and maybe we can meet, though I have a class elsewhere that Thursday.
ali