I would like to know if it is economic to fit a car with Air Conditioning. Also , are there any pitfalls to having air con that people have come across?
Air Con uses a reasonable amounto f fuel, and systems can be tempremental, and expensive to fix. If you haven't got it fitted by the factory, I wouldn't bother - you can open the windows for that two or three days of the year we call summer!
It can be fitted by an independent company if not fitted as a manufacturer option. It's not cheap - several hundred pounds at least and in my opinion won't be quite as effective as the manufacturer fitted version. As mentioned, the compressor will take power from the engine and therefore, increase fuel consumption.
Not every car can be fitted later. Check with the main dealer or an a/c company to find out for your particular model. Small cars in particular can be problematic. And i love my air con, especially in summer on motorways which are smelly with the window open. Its also great for helping to demist the wondows quicker!