What would be better would be a contractually agreed-upon number of gallon prepurchase. That way, you know exactly what you're getting. The problem there though would be who knows what happens where a porter says the X gallons didn't return the car to full and then you get charged for the difference. I really don't think there's a good solution to this...which is why I will continue to fuel it myself!

But whoever recommended the GasBuddy app - cannot recommend this enough. Makes refueling prior to returns a breeze. And generally most gas gauges give you a minimum of 10-20 miles you can drive before that needle moves anyways, even more on the highway. Not to mention, if it's a short trip and you're only putting in a few gallons anyways...does the extra $1 make a difference between the more expensive and the cheaper station?