The van I drive, a Toyota Sienna, gets pretty good gas mileage . I factor distance/time and what I will be able to sell the item(s) for before pulling the trigger. I listen to music and relax while driving around. I avoid rush hour traffic if at all possible. I drove approx 15-20k miles this past year picking items up and delivering them. It's by far the biggest cost. However, that's pretty much my only overhead, as I sell the items out of our garage/house for now. (I've gotten pretty good at knowing what will sell and what won't, so I stay away from items that I will have to sit on for a while or are difficult to store.)