TrueCar has a price that they evaluate the car at, and they give you a slip of paper that you can go into any TrueCar dealership and buy that car from them at.

With this method, sometimes the car dealership sells a car for lower than they were hoping with the local market, and sometimes they make a killing off the customer.

CarWoo, on the other hand, asks each dealer individually what they want to sell the car at, and then forwards that price to the user.