You could try looking into a 2004 HONDA CITY or JAZZ 1.3L M/T.

It gives one of the better FCs among small cars available in the local market. The A/T CVT version actually is better but there is an issue with long term wear & tear with the transmission.

And if the frugal FC is not enough for you to save money, you can have it converted to Auto-LPG.

Example: Honda City 1.3L iDSi - AUTO-LPG conversion
http://tsikot.yehey.com/forums/showthread.php?t=51321

In the link posted above is our Honda City converted to run on Auto-LPG. After nearly two years, so far it runs well with occasional "hiccups" which generally requires a change of spark-plugs (or cleaning the existing spark-plugs) to return to normal.

BTW, the car can still run on gasoline. We just need to press a button to switch between fuels.

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