I found that the Costco pricing was generally in line with truecar.
I used the Cco program with a dealer slightly out of my area but i stopped at the local dealer (where I had purchased a Toyota previously) and when it was all said and done, the local dealer was slightly lower than the Cco pricing.
Their trade-in offer was lower though so I went with the more remote dealer.
I bought the last 6 cars through Cco and felt I always got a good deal. The Rav is a 2016 Limited HB with the TP. When I went to the dealer they did not have any in stock and were not giving a discount, but were bumping the price up by a 1000.00. Don't know why, but they ordered one for me and in the end took 2000.00 off. As part of the deal Cco gave me a gift certificate for 200.00 in auto parts, which I used for accessories to the Rav. I think I got a good deal on a great car.
I purchased my RAV through the Costco program. I got a slightly better deal than I could work though my previous dealer where I bought my 09 Venza, but also got $1500.00 more in trade for a flawless trade in.