Regarding the 1 lakh car, all knows that TATA offers an Indica in 3 lakhs, now imagine what they will offer in 1 lakh??? Huh... may be a car that runs on motorcycle engine with a kick start or with pedals... Forget it that it will have an AC or a power steering which are actually a necessity, not luxury. One can ride a bike in open but its difficult to drive a car without AC. If you can buy a new car than nothing is better than it but only Indica is available in this option(CNG) and it is not advisable to get CNG kit fitted in new car as it voids warranty. As per your daily driving, if you buy a petrol car your monthly expenses will be around Rs2500 and less than half of it in case of CNG and it is a cleaner fuel also with no emmision of green house gases. But then fitting a CNG in a used car will cost Rs 40,000. Alto will not be appropriate because it has a very small boot to accomodate CNG tank. A wagon_r or a Santro is more advisable as a used car and to fit CNG, a Maruti make car will furthur reduce maintenance expenses.