It used to be that all Bar/Bat-Mitzvah parties were formal, sit down parties with music and dancing, catered with various courses to the meal. You would invite everyone you were related to, all your friends, and some acquaintances. Nowadays, that has changed quite a bit, and while some people still have traditional formal parties, many are choosing to have a casual party instead.
Casual parties are much, much easier to cut down on the expense. There is much less labor involved, and the food can be more casual. For our daughter, we have chosen to have a bowling party with a 50's bowling theme. We are renting out a section of a local bowling alley for $300 per hour which includes bowling shoes, 8 lanes, and a lot of casual seating at tables and couches. The bowling alley is providing us with a buffet of pizza, and salad, and soft drinks that is not going to be kosher, but it will be vegetarian as to not have to deal with non-kosher meats. This will be fine for most of our guests. The cost of food and drink is still not cheap, but $13.95 per guest with unlimited pizza.
There are other options we can add, like a disc jockey, a bar tab, game room tab, and an extra room. Most likely we will chose not to include these, and if guests want to use them, they will have to pay. We are going to create a personal 50's video that will run during the party to help further the theme. This only adds $50 to the cost.
In comparison to the big party we hosted last time, the fees this time are much less. For our first daughter's party, we had a large room ($400 for the night) with tables and table clothes, and huge buffet, with a DJ who was amazing (but cost us $2000 just for them).
While this time around our party will be a bit smaller in stature, I think that we will have just as much fun, for a lot less money.