I knew what I wanted also - the best car I could get for the money (they were all the same price). I also wanted honesty. I didn't try to haggle them on price...but wanted to make sure I got what they said I would.
Just make damn certain that he knows you will go over the car with a fine tooth comb. I know for a fact that the majority of the cars there were not perfect. NOW, with that said, most of them were 'close enough', meaning they could be easily repaired. You have to keep in mind that you are buying a car at half the sticker price. Also, your version of 'perfect' and my version could be completely different. I worked in a body shop for a few years and I am that guy who will get down on my knees (in the gravel at Bonham) and catch the reflection just right to make sure there are no dents or prior body work.
Oh yea - expect some tape residue on the interior of the drivers door panel. It was on most of them.
Jeff and Sean were who I dealt with. It took me two weeks (over the phone) to get them to say they COULD certify the vehicle. Their excuse was that they don't ever certify them. I finally called their service department direct, and they told me within 10 seconds how much certification costs.

And, remember, DO NOT buy the chrysler ESP from them...they will gouge your eyes out. My finance guy was named Tracy and he was absolutely horrible. Secure your own financing if possible.
If you have any trouble with warranty or paperwork, call Jan - she is in their accounting dept. and is by far the best to deal with.
Like mentioned above, the dealer is basically placed in the middle of farm land. There is a lot of wind, a lot of dust, and a lot of gravel - this makes for dirty cars. Make sure yours is rinsed and stored inside prior to the day you arrive. It is easier to find defects when they are clean.
There was also a car, when I went, that had the window down and apparently some rain and dust got inside at some point...
My car had 18 miles when I picked it up. I am 300 miles away in San Antonio, or else I would definitely check it out for you.
If it matters any, there are two roadsters near my house for sale, on graphite and one black, both $25.9 with 10-12K miles.
LantanaTX is up that way towards Dallas. You may ask him if he is heading east at all...he is a stickler just like me and could easily go over a car if he is headed that direction. You could also pay for a 3rd party inspection.
SQ