Fernley is the place, more than one station. Gerlach is just a cluster fuck on the way in, and if no flagger is up it gets a little worse. Also keep in mind the Gerlach station is going to be jacked up in price as well. However if you must get gas then do it. Also on the way out it's a little better if you do what gate radio tells you to do to get gas.
I come in from the west through Reno and always stop at the Greg Street exit (easy for me to remember) just before leaving the city. There are a couple gas stations there on the north side of the freeway. I fill up and have enough gas to make it to the playa and back to Reno after the burn. Avoid gas in Wadsworth, Nixon, Gerlach unless you want to get stuck in a big cluster fuck!!
The place you're renting from should have a pretty good estimate of gas consumption during driving and for a week's living. I'd ask them and then add a little to whatever they say it will use just as a cushion.
It's my job to educate Sparkle Ponies...I'm not nice about it...don't be a Sparkle Pony and we'll get along just fine.
what I learned: I barely used the generator in the RV - maybe like, 6 hours the whole week and that was mainly to charge things / run the microwave. i think we used the AC once and it was probably not even really necessary.
topped it off at the gas station / highway robbery joint in gerlach. that was more than sufficient... could have easily gotten in and out with the gas i had at fernley, and that was with an 8+ hour exodus.