Splash: Divided into 85 cars = £17,000 per car. Vauxhall Astra's start at about £15,500. Then there's the insurance and service costs over 4 years.
I'm pretty sure if you were to buy 85 cars you'd get a significant discount. It's called Fleet Sales.
Another thing. The WTBTS doesn't necessarily have to make a huge profit on this. But notice that the Society has a large number of activities going on in which they profit: cars for COs, hotels for conventions, purchase of equipment for jw.tv broadcasts in the congregations, and of course the biggest money maker: their real estate activities!