At least you don't have to worry about overhead clearance!
As we were leaving Mesa Verde National Park a couple years ago (and eating breakfast in the cafe near the campground), some poor soul pulled his trailer into the gas station there and unfortunately, the AC unit was just a bit too high to fit under the roof over the gas pumps. There was a loud "crash", and he stopped. Sadly, the AC was pretty banged up and it pushed down into the roof of his trailer. I think he would have been able to back out if he let most of the air out of his trailer's tires, but we didn't hang around to see. It was one of those "mansion on wheels" kind of rig that I'd hate to be pulling.
In all honesty, I've never found gas stations to be much of a problem. Just make sure you have a straight "pull-through" like Rich said and you'll be fine.
His advice about the tanks was spot-on too. While we hardly ever camp at a full hookup site, I never attach the drain hose until I'm ready to completely empty the tanks.
Hi-Lo 1707T - Tire Minder TPMS on Tow Vehicle and Trailer, 300W Solar Battery Charger, Equal-i-zer WDH
2014 F150 Platinum 4x4 3.5L EcoBoost SCrew