I'm with SoundGuy, what would you really learn from a test drive if this is your first TT?
I was in that position a year ago and my TT was a resale on consignment and the dealer did say YES. I towed it without a WDH and no brakes (or even lights). That was with my wife's 4Runner which really was too small/light to do a good job in the real world.
What I know now, after over 3,000 miles of towing with my Expedition, is that test drive was dumb/scary thing to do. I had nothing to compare it to an all I knew was I was able to accelerate, turn, and stop. And not particularly well with any of them.
From staying next door last year, I know the Lazy Days in Tucson does classes for beginners. It may be worth checking with them or someone closer to home to see what that entails.