In the first place, any party this size requires 4-6 people in the kitchen and about 20 people out front day of to set up, serve, and clean up a party this size. Are you prepared to hire (at over $100 per person, on average) and run a crew this size?

It requires a commercial kitchen with a full walk-in cooler, and at least 4 serving lines- 6 is better.

In addition, a wedding reception has to be perfect; it is the most difficult of all catering jobs. You can ruin this once in a lifetime day for the bridal couple and their family if you don't know what you are doing. It is usual to spend 6 months working on the plan for a reception this size.

You don't say what time of day, what meal, what menu? What budget? What restrictions as far as foods, beverages, etc. What is your background and experience? I can't help you with a menu when I don't know what you want.