I think it depend’s on how much you are makeing and how much you can AFFORD. $50 is good for some, $100 for other’s. If you are goeing to the wedding with a GUEST, you should give MORE then you would if you are goeing alone, or NOT at all. After all, it costs money for catering and food and renting the hall or church or whatever, and DAD says that you absolutely HAVE to grease the person who marries’ you ahead of time so that he does NOT embarass you by saying the wrong thing before you get MARRIED!
It is very easy to be a MAN (or woman) of the cloth, Dad says. He says that peeople get very nervous when they have a religious ceremony, either a bris, a wedding, a bar mitzveh, confirmation, or even a funeral, and the man of the cloth MUST be good and get greased. I think you must get a steady handed guy to do your son’s bris, otherwise your son (and those women he eventually dates) will never forgive or forget you. I remember my FIRST college room mate went out with a guy who got a bad bris, and she did NOT want to date him just b/c of that, and that was about 18 or 19 year’s later! FOOEY!