Its very sad to see a lot of negative reviews about ford Ikon. Ive been using Ikon 1.6zxi for the past 10 yrs. I am getting a mileage of about 13 without ac in city and 17-18 in high ways, when I am going in a constant speed of about 70-80kmph. It all depends on your driving skills.
Maintenance - try a good mechanic nearby or built up a good relationship with the mechanics working in ford service station. Giveem some money they will come to your home to service your car. It works out for me. Spares=yes the spares are costly when compare to others (Maruti 800.1000.esteem) at the same please check out the spares for Swift or baleno Indica turbo or vista or fiat Palio. The spares are all more or less equal rate.
Ford is always known as the Drivers Car. If u r going for a long trip. use the full AC for 10 minutes and turn it to 1.this will increase ur mileage. Use proper tyres/ drive in a constant speed with correct gear dont strain the engine /fill petrol in a regular station in early morning.
All the Best.