<human>: Not sure who else I can ask this, without sounding socially inept and since I can't ask the birthday girl herself, here I am... My best friend does drink. She's by no means an alcoholic, but she does like to drink when she goes out...I on the other hand don't usually go out or particularly like the bar/club scene, which is where we will be going tonight. She turned 22 today. Anyway, funds are low...well to be honest I don't have any money, except that I am borrowing some money from my parents till I can pay them back in 2 months. Anyhow, I don't want to be cheap or seem stingey, but do I buy her a drink? or a shot? which one is cheaper? I'm not even sure what the difference is...but the thing is this friend...if I tell her to choose the drink, I fear she will choose something that's more expensive (she's taken advantage of me like that before). this is why I'm wondering if it is customary that I should buy a drink/shot for her birthday, I want to get something that is on the cheaper side. So, I'm not sure if that means I get her a shot or a drink or a margarita perhaps? also, how much do you typically tip the bartender? thanks reddit! I still have to buy her a b-day gift too, so I need money for that.

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<bot>: friends birthday today. do I HAVE TO buy her a drink? if I do, what's the cheapest thing that is decent that I can get for her?