tips for buying cars (Abu Dhabi)

Hello AUH!
Me and my husband have not decided yet whether to buy a used or new car. We've been reading lots of news that this is a good time to buy used cars since lot of people in DXB are leaving and want to get rid of their cars. However, since we have no idea about rules on registration (since we are living in AUH), plus I'm afraid that the used car could give us problems later on.

Could anybody guide me how to buy cars in AUH? pros and cons on used & new cars please....