For that kind of difference in price, it usually comes down to the brand, which breaks down to additives, and so on.
I’m a fuel snob and have been an import tuner for 20 years.
It’s no secret. Not really.
What we see on the dyno tuning a car filled with Costco or god forbid Arco, versus Shell/Chevron etc. confirms the tech, fuel folklore and even our own naked eye and hand observations.
@w_s_bitcoin My bad. I misread.
Have you done an exterior inspection on points of entry? Usually it's fixable small stuff like closing up gaps in a wide ranges of places on the homes structure.
Mice need about a dime size to enter.
Rats about a quarter.
Hope ya find it soon!