Just checked Suzuki Swift base model it is 12,20,000, go for it or buy a 2009 Honda City, but id say go for a brand new car, go for Swift, stay away from Wagon R if u have a budget of 11 - 12 lac rupees.
And about fuel economy, if you are burning 4 liters a day on a mehran, you ll be burning no more than 5 liters on a swift, so that is no big issue.