Selling a Car in General

I have bought and sold many used cars over the years and I've noticed a lot of people have problems on what to do with an older car when they get an alternative.

1. Clean the car: I'm not looking for show room quality, but when I go to look at your car, I don't want to see all the food you were eating over the past year or the all the cloths thrown all over. And a wash would be a great idea too! You don't need to hand wax it but even a standard car wash is enough and can change the feeling of the car. Also clean the rims manually as the automated wash will not get the brake dust off.
2. Hmm what's that noise: When it comes to the mechanical side of things, you should have a general knowledge so you don't get taken. Maybe you need to find a good mechanic and become good friends with him! These people can be hard to come by (I have seen so many shady things while repairing cars - lots of nightmares) so when you find one, do be nice!
3. Negotiating: This is one of those life skills you should develop and know the game as it unfolds. I can't go into too great of detail here as this post would be very long. Here is the short hand version: you need to know what your bottom line is and need to negotiate as that. The buyer may suggest that your price tag is inline with what others are paying for similar vehicles, but he want's to pay less because this or that problem. Know that *ALL* used vehicles will need repairs of some kind and to find a mint condition vehicle for the same price as your beat up jalopy isn't going to happen so use that to your advantage.
4. The paper work: This you will have to do some research before hand into what needs to be filed and where. It's more complicated in bank loan than in straight cash deal where you just sign an agreement in front of registration authority - RTA, Tasjeel, Shamil or Wasl in UAE. 

You would be surprised at how often these items listed above are overlooked. If you're savvy, perhaps you can squeeze a little more money from your old car or at the very least get the fair price your car deserve.