Dublin is an amazing city. The people are very friendly and helpful.
Be sure to get out of Dublin and visit some of Ireland's other beauties. If you don't have time for travelling outside of Dublin, Howth is the perfect place. It's 15 minutes from Dublin by train and it's a whole different experience, but be prepared to walk a lot if you want to see the cliffs
Insider Tip:You might want to be prepared for any kind of weather. Wear layers in clothes, as the weather can get from cold to hot or vice versa in a matter of minutes.
As far as the money is concerned, the alcohol is quite cheap, but the food is pricey. If you are not willing to spend some money, prepare to starve.