I'm going to make this a long one since it caused me some unnecessary $ basically saying their diagnose of my problems were very very bad. If you have time read on .
I've been in the car business for more than 8 years now and I've had my share of experience with all kinds of mechanics. If there's one rule that I have found to be true is that a cheap mechanic is not a good mechanic, a good one won't be cheap! But these guys are not good and definitely not cheap. I have an Audi & a Benz and both had some issues.. So I was looking for a reliable mechanic. I saw these guys on Yelp and I was blown away by the reviews. 70 positive reviews (for a mechanic!!! Wow). I had to check them out.. So I went with the Audi since it was due for an oil change.. I also told them to check why the battery & fuel cap light came on when you start it in the morning.. Next day I pick up the car and was told the alternator is good but I needed a new battery for sure.. So I did just that.. Went and got one ($160) and replaced it.. Well that didn't fix my problem but I didn't make a big issue since these things happen.. After all everyone else says they are great.
Now it's time for my Mercedes that is stuck in 1st gear and won't shift. I had charged the auxiliary battery at Autozone in hopes to fix it myself.. it didnt (I read that this is one of the most common reasons what causes the limp mode). In the process I switch the cables backwards so it triggered the battery light. I towed it to the shop and asked them diagnose and fix the issues. After diagnosing they said I need to replace the auxiliary battery and clear the light/codes and then they can see why transmission is not shifting. Quoted me $215 for the battery and programming. I went & picked it up at the dealers ($115) and asked a Mercedes mechanic whether an auxiliary battery needs to be programmed or not. He said never. If the code/light is still on just reset it with an OBD scanner (which I do have) and that's it.. I told the guys at CARS that. They said 'No no.. he doesn't know what he's talking now about we still need to charge you $50 for programming'. OK no problem, do it. You never want to argue with the guy that is about to fix your car or cook your meal. They called me & said transmission is bad. At least $3500-4000 ($800 labor) to replace it. I know enough for a case this big to get at least a second opinion. So I went to Doctor Benz (a shop that specializes in Mercedes cars) and described the problem. He raised a red flag: if they are charging for diagnosing they should at least tell you what exactly is wrong in the transmission. In this particular car you almost never change the whole transmission. He wanted $200 to open the transmission and see what's wrong & that's used towards the total if I decided to fix it with him. With worst case scenario $2000 total if the module is bad (most of which is labor @ $125 an hour). As I left from there literally the next building there's a transmission shop so I just stopped by to get a third opinion. He repeated the same thing but he was going to diagnose it for free! So I towed the car to his shop to find out that CARS didn't even clear the battery codes. They sure charged me for it! That's because it wasn't the battery, it was just a damn fuse!! Once we replaced the fuse the code cleared. Two replaced batteries for absolutely no reason! I also called LKQ to check for the price of another transmission and see how reasonable is CARS with that $3500-4000 quote. LKQs price for a transmission with 61k miles $1450. With 100k miles, $1150. Now to be fair I do get discounts on parts at some places but not a $2000 discount ( a few hundred the most)!
I gave the second star because they all have a friendly attitude & advised that since I already replaced the fuel cap the next thing to do was to replace the purge valve. That fixed the fuel cap problem.