Hello!
Hello
On my upcoming trip, I would like some extra food and water for my family.
Ok. I would like to have some extra firewood.
Do you have a preference between food and water?
I would like water more than food. 
How many wood do you think you need?
I would like 2 of the firewood. What do you think? 
I don't need wood as I am usually warm so I think we can work out a deal. I like to have more water and I usually get thirsty.
That sounds good to me. 🙂 I think we can make a good deal.
I can give you 3 wood packages if I can get 3 water and 2 food. So you will receive 3 wood and 1 food. What do you think?
I would like 2 wood, 1 water and 1 food. You would get 1 wood, 2 water and 2 food.
I don't need any wood. Do you have any alternatives? I think my original offer is fair. I want you to have your most desired item (wood) and I get mine (water).
Ok. 🙂