In my experience, it's not always 1.5-2x the cost of a full tank to pay up front. The last time I rented, which was a couple years ago, it was only 10% more, we

In my experience, it's not always 1.5-2x the cost of a full tank to pay up front. The last time I rented, which was a couple years ago, it was only 10% more, well worth the potential BS, and I returned the car with like 10 miles remaining on the dash, no worries whatsoever. That's not to say rental agencies don't universally suck, they certainly do, but, I wouldn't really say that's a major sticking point. Really the biggest problems seem to be them under-provisioning their fleets, and going after you for damage you didn't cause, both are far, far too common.