If you do not have an experienced team, it would be very wise to consider having the meat catered and doing the rest yourself; still a good savings, but MUCH easier for the home team. Also, there are other meals that are simpler and less costly than bbq sandwich meals.

please read the article on catering your wedding dinner on this site.

www.ellenskitchen.com/bigpots/plan/wedding.html

Then you can write again with the details- such as where will you be cooking and serving, appetizer plan, how much help, rental of equipment, alcohol or no?

If the budget is very tight you would be wiser (and would please your guests better) to plan a very nice reception or brunch and schedule the wedding appropriate time, rather than a thrown-together dinner.

Also with 160 people at a wedding, you need to plan an appetizer area; this is discussed here:

A self-catered buffet is a real challenge to the organizers, and things don't always come together as smoothly as hoped. By planning and setting up an appetizer area or "nibble table" which is ready when the guests begin to arrive, the cooks and servers have time to complete the arrangement of the dinner buffet. This is especially critical if there are children among the guests, or there is a wait before dinner, as at a wedding reception.

This does not have to be complicated. Three items, plus a punch, or two if one is alcoholic, are sufficient. Typically, include a fruit tray, a cheese tray and an attractive dip or spread; or you can go with a dinner theme such as TexMex with chips, salsas, Texas caviar and guacamole; Italian with bruschetta or antipasto; maybe shrimps or other cold seafood, if budget permits.