Do you have to test drive a vechical before you purchase one

You don't have to, but I would highly recommend it.

It would be stupid not to but go ahead and suit yourself.

It's not a requirement but I would recommend it if buying locally. If buying long distance have the vehicle inspected by a professional inspection company. I've used lemonsquad.com in the past with excellent results. When I bought my 94 Fleetwood it was a long distance purchase. I had the car inspected by lemonsquad.com before I decided to buy it. They test drove it for me. Hope that helps! Jim