Stealing Gas

Hans Hartwig,  one of my summer students here in Leipzig, submitted a short piece on stealing gas out of a tank as an unsolicited attempt to gain extra credit as an addition to the mid-term test grade.
He wrote:
"So just this past week, my sister was driving back from Washington DC to Wisconsin. Of course Dayton is exactly in between my hometown and where she lives in DC. So a stop in Dayton overnight and a visit to the Pine Club was necessary.
Unfortunately, while she slept at the Marriott, someone siphoned her gas and she lost almost all of her tank. I wanted to do a little research about how to protect my car from gas thieves when I return to Dayton in August.
Here are a few I came up with.

1) Buy a lock -- most of them cost between $10 - 20.
2) A company called Tiss makes fuel tank safeguards that allow for refueling w/o a lock and key system.  Effective on almost any fuel tnak. company based in UK.
3) avoid the use of gas altogether. use public transit, a bike, or an electric car to get around.
4) Have a button installed that locks the tank and can only  be opened on the inside of the car.