Do you mean lowest price or something else? "Best" is subjective and depends on several other factors. Some of the cut rate rental companies want to endlessly haggle with you about adding needless upcharges or have limited hours so you might have an issue returning the vehicle. The more reputable rental companies don't pull those stunts.
Ditto, ditto, and ditto! Budget is often cheaper, and they are OK, but we had difficulties with the toll roads because the transponder wasn't off like the switch indicated. Even if you use it once, they charge you daily for it. It was a hassle to undo, but they did in the end remove all excess fees.