I will always give them something. I know that a tipped position (cocktail servers, waiters and waitresses) minimum wage is just a little over $2 an hour in NJ which has a higher minimum wage then some states. Therefore, I always tip them no matter what. How much depends on the service and it is also dependent on many factors such as attitude, if they are not busy were they over checking our needs, if they are busy then I am forgiving, if the food was incorrect as long as the problem was nicely corrected-I look passed it. If they were downright nasty to us, then they get bare minimum for tip. If they had a great attitude, were busy but did their best to take good care of us or not busy and were very helpful, then they get the best tip-I can handle mistakes, we are all human but it is about how the attitude is. If they brought me the wrong thing but they were nice or funny and corrected it, it's cool. If they got a bad attitude about it, then we have a problem. If they are good (mainly great attitude-can take a joke, smile or even make me laugh), I have been known to give more then 30%. I also base it on the bill, if we only ordered breakfast that came to $15, it is not their fault we didn't order much. If they gave us great service, they will get $5-$6 on that $15 bill.