Crazy Climate Controls (84 seville)

[rotarybuddy]

Hello-
I have an 84 seville with the electronic climate controls and when put on auto to be warm it runs cold and when it is put on colder it blows sort of warmish air. Also the AC compressor does'nt turn on and there may not be any refrigerant. The car sat for a couple years and has 33K miles on it. I am fairly mechanically inclined, but Iam trying to sell the car so I do not want to get into costly AC repairs that require a shop. How easy is it to refill using a kragen type kit. Where can I start in diagnosing so if I do have to take it to a shop it is as straight forward for them and as cheap as possible for me. Thanks