- Be aware, if you use the ParkWhiz app instead of the ParkMe app (which Colonial allows), the Colonial attendant may not know that's valid. I spent 10 minutes arguing with him that I was directed to ParkWhiz from the Colonial website until he finally relented and called a supervisor who told him it was fine. I've had problems like this with Colonial attendants before. Wish they didn't have such a monopoly on garages in DC because I wouldn't use them otherwise.