I hope someone, once and for all, can clarify (with examples) the difference in usage of will vs. would vs. would have vs. will have.
This question is quite broad, and I find it quite hard to come up with an answer that is comprehensive yet succinct, technically impeccable yet easy to understand. At the risk of failing miserably, I'll give it a try nonetheless.
Will, would, and have are auxiliary verbs used to form different tenses.
Will is used to form Future Simple, to describe something that takes place in the future.
Will have is used to form Future Perfect, to describe something that not simply takes place in the future, but is completed ("perfected") at some reference point in the future (which is usually specified).
Would is a past-tense form of will. If you are writing about past events, you can use it to indicate something that was in the future at that point in time, but is not necessarily in the future right now. In other words, you use would to preserve the future aspect when talking about the past.
Would is also used as a modal verb to indicate a conditional or subjunctive mood, or to "soften" what is being said:
I realize that I have omitted a few things (say, Future Perfect Continuous). Again, that was a conscious decision for the sake of simplicity.
The articel Will you or would you? gives a few examples.
Will have or would have you might find useful.
"Would" has two meanings and I'm not sure which you mean, but one is a modal verb and conditional.
The other one is past tense and basically just means "used to"
"Will" is for certain.
Adding "have" to the end just makes them the perfect tense, which kinda references the past too. I'm not sure it works with the conditional type of would, but I could be wrong.