If you can opt to use a container that has a diameter such that you can do 3-4 traps say 1.75 per time and deep enough to cover say the same number of longsprings with chains etc. That way you can wax a lot of traps with say 10 lbs. as your starter base and you can add a lb. as needed.
If you use a very large diameter kettle or pan you will need a lot of wax just to cover 1 trap.
By having a smaller diameter container you will also have a larger volume of the wax near the outer surface and thus it will not get as hot or as likely to smoke and burn as if you are putting a lot of wax into a container that will hold more heat in the center mass of your wax.
Bryce