How to write a paperCatering a barbecue to 500 people in a wheatfield with no water, power & sanitation is a tall order and a challenge. Nothing is impossible. It's whether the party is willing to pay. Get the people from the food & beverage be involved in the brainstorming.
I'm a retiree with no food catering experience & this is what I'll do.
First, has the wheat been harvested? You do not want people trampling all over the fields. Does it require a permit?
If this clear, ask their orgainising committee to sit down together to discuss needs like type of food spread & drinks, etc., etc., etc.
2. Need to pitch marquees to hold 500 people and long tables to hold the food. Are guests to be seated? Do they need to be served or is it self-service. Enough chairs.
3. Don't forget a marguee as a kitchen.
4. 12 Portable toilets marked for 'Ladies' 'Gentlemen' with a partition to block the view from the guests. Keep it at a distance from the main marquee. Not everyone will visit the toilet at the same time.
5. Need a power generator.
6. Have enough drinking water, hot and cold drinks in containers fitted with dispensers.
7. Water for kitchen area and the toilets. I think one truck load water will suffice. Get in touch with the Water Department. I'm sure they are able to help you with people who offer such services.
8. Garbage bins in stragetic positions.
9. Food to be pre-cooked and placed in warmers.
10. Any food that need to be barbecued, set up barbecue stands with assistant cooks to attend.
11. Do have enough assistant cooks, waiters & waitresses.
12. How many man hours needed to set up the place?
13. Consider other factors and do your maths correctly.
14. Submit your quotation listing all the breakdowns.
i. food & drinks charge at per head
ii. cost of setting up marquee
iii. cost of portable toilets
iv. cost of transporting water
v. charges for rental of power generator
vi. No of waiters & waitresses provided
Throw in some freebies, like soft drinks & decorations
Give a deadline for their confirmation and ask for a non-refundable 50% deposit,
Consider too, whether you are a small caterer. If project is too big, work jointly with another caterer.
It will be no sweat after one experience.