I guess the big challenge was to find a color scheme not being used by one of the cab companies. I didn't care for any of them. I remember the first time in DC in 1989-90 seing the different models used for cabs. I remember Pontiacs, Buicks, Olds, Mercurys, and smaller cars like Toyotas and Hondas being used as cabs. It was quite different than I would see in Philly or New York. It did add a little character to the city.