Cash bar okay at a birthday party?!
Yes it is ok to have a cash bar. You are going to be offering non alcoholic beverages right? Let the alcoholic drinks be an option to your guests but make sure they are at good prices! See if the bar will set up any drink specials for your party!
I think that if it's a full bar, and not like drinks thrown together then it's fine to have a cash bar. Just let people know.
You could also do a BYOB on the invite if you can't really afford the open bar, and let people bring their own (that way you aren't responsible at all if a drunk person leaves your party and gets into trouble)
Unless you are having a formal bday party. Then it might be different.
I would not mention the open bar on the invitation. It will be plain when they arrive that if they want alcohol, they need to go to the bar to get it and pay for it. I would also make sure you and your husband, as the hosts, do not drink alcohol during this occasion, lest guests think you have a tab going.
I think that's ok.
Make sure that you tell everyone on the invitation what dinner includes for free, and what is extra, just so that there is no confusion.
Yes it is....