[marla]

We have two cars. We always use the smaller one for running around town unless we need the bigger one to haul things. We used to use whichever one we felt like at the time without much thought, but realised we were spending an extra $50 a month because of all the gas the larger vehicle consumed.

I always turn off the car. I used to let it idle because I knew I would be back in a minute. One time I went into the store and starting talking with a friend. I came out an hour later to see I had left the car idling. What a waste.

We keep track of gas mileage. If the gas mileage drops unexpectedly, we know something is wrong. We have caught two potentially expensive repairs this way before they became expensive.