What is the official length between posts when building a chain link fence?

The fence is 6 feet tall if that helps. Please answer only if you know for sure. I will choose a best answer.

When building a privacy fence, what is the proper spacing between the planks?

I vaguely remember someone telling me to nail the planks together with no gaps because the wood will weather and shrink to form small gaps between. But if the wood is pre-treated, is it going to shrink?

When building a fence is it necessary to have 3 support railings between post? I only have two between post.?

I’m planning to screw the pickets into the rails. They are 6′ dogeared pickets.

What would be the cost differance between building your own fence or paying some one?

I have about 100 feet I need to fence with one gate. I dont have any tools and its just me and a friend. We wre quoted $1500 to do it by a contractor. But I was wondering how much cheaper would it be If I did it. I also have about 75 feet old [...]