For a card (not the AGR) I never use, I keep it active by automatically having my wife's few mail order medications charged to it. Couple of times a year it gets used and it, like all my cards, get paid off immediately.
Going to make a killing on my AGR. Having to put in a new HVAC in the house. $11.5K. Half down and half on work completion. First half went on AGR. I'll pay that off before it is due by sending a echeck immediately so the next CC bill is not high (or hurting credit) then do the same for the rest. Just as easy as paying by check but I actually have more protection. And I get all those points! Nearly 12,000!