Four is a good number!
Heh...our local grocery offers a 10% discount if you buy your wine four bottles at a time. I admit, I’ve only done that once. And they always pressure me a bit to pick up a coupla more bottles if I just buy one.
I’ve never bought that much at once, but I’m not really supposed to drink anyway.
I only get a discount if I buy a case at our local wine dealer. I rarely buy that much at a time.