Originally Posted by
BAGoldBoy
I have tried this and also valid zip codes but have never been accepted - usually send SWMBO in with her card but some garages very unhelpful and want the gas prepaid so difficult if trying to return a hire car with a full tank

That is indeed rather useless. Sometimes I've gone into the store, hand over a credit card and then filled up the car (before I found out the 00000 trick).