How many times have I asked a sales person, "Have they driven the car?" Do you have any idea how many times I hear, They drove it at the other dealer or they don't have time to drive it or my favorite. They already own one that is three years old. Really? You are going to waste all that time on a write up when your chances of closing a deal without a demo drive is about ZERO! (Okay you fleet people with huge corporate accounts. You are not in the conversation.)
If you are having trouble getting the customer to drive... just have them sit in the passenger seat, start the car and pull out. That was easy!
Chances are they want to drive, but their walls are up, they want to say no. A demo drive is one step closer to the sale and they know it! DO NOT ASK! Say something really cool like, Hey, lets take this one for a spin or Get In!. Anyway you do it, you can't close the deal without it.
If the prospect will not drive and just wants to work numbers, that's easy. Tell the prospect "NO!" and follow with, "I really don't like to work numbers on a car you may not like, I let everyone drive before I work numbers." (It could even be company policy, they love that.) This is the line of last resort for me... find your own, but please, find one.
Now about the drive itself. Always turn right. Look at a way to do it. Don't let your prospect get sidetracked by traffic. Figure out a way to make all left turns happen. Drive the route yourself first. Point out all of the features you want them to focus on during the ride, find a safe place to switch and perform the drive again. (You might want to perform another quick walk around when you switch.)
You know, I feel so strongly about the demo drive, if I can't close the deal on the first presentation I will generally offer up the demo again.
All in all... here is the bottom line.. Do it or don't. If you want to succeed you will!