How I know I have played too much GTA: I was driving behind an armored truck this morning and had some pretty nefarious thoughts... There was traffic in front of me and I thought I could squeeze through the gap in between the cars...
I checked the location in the video at a few different times during the day and night but only saw G-wagons and Audi's. Dunno what kind of randomization goes into the placement of vehicles. Also, not really a rare find if you can buy one with your cell phone. Once you finish the missions and buy the properties you have fuck all to spend your money on anyway.