Does your car have a broken AC unit?
It is best to find HVAC service shops or garages in your area when your air conditioning stops working in your car. The last thing you should do is to take your vehicle to just any garage or dealership for repair work. You honestly want only certified heating and air mechanics looking at your vehicles AC unit. Not every shop or garage has these type of mechanics available.
Now, most car dealerships do have a central air system mechanic available at all times. The only problem with taking your car to a dealership for repair work is the cost. It will most likely cost you almost double for the air conditioning repair work. Unless your vehicle is still under warranty. If this is true then you may not have to pay anything out of your own pocket.
The one true benefit to having a dealership do the ventilation repairs is that you are guaranteed top-quality work to be performed. Even if the work does cost you a little extra at least you know it was done right. Now, do not give up on small garages though. Often times you can find one that has the knowledge and certificates to perform the work. When you find one of these you have truly struck gold.