M.,
I have 4 kids so we only do b-day parties every other year. On their non-party year they get to invite 2 friends over for dinner, cake and a movie. For the party year we have a $100 budget. I don't buy goody bags for the kids I invite. I make my own cakes- we have a blast decorating a simple 9X13 cake. I have never felt the need to entertain adults- I mean I offer them soda or coffee and maybe put out chips and dip if they are at my house, but never anything if we are out. I also have never felt the need to invite everyone in the class, Sunday school etc....
Some places that have reasonable parties are Metroplex Gym, the local parks and rec center, and Pump it Up.
At 2 I invited 5 or 6 friends to McDonalds bought them all a Happy Meal ( $20.00 ) and let them go crazy on the play equipment. We brought in our own cake- had a blast!
Remember she is 2- she has NO expectations. She just wants to have some fun!
D.