It is quite hard to explain but In this sentence my feeling is that it is related to the pattern, 要是。。就. which is used to explain the consequence of an action. It is explaining that if you tell me beforehand, (就then) there will be no problems.

Yes, here the word like "只要" in "只要，就" is hidden. So it's part of "if". Suppose if you say "if" as "if..., then...", 就 means the "then"

It's a adverb which is used before a verb and it means it will be like this automatically under some conditions,kinda like "then" 不斗争就不能前进(if ou didn't work hard, you would never get improve) 只要认真学习，就能取得好成绩（If you work hard, you will get good academic performance) 要是有房子就好了（If only we owned a house)

then. if you told me ahead, then it would be ok. otherwise you're in trouble.

Sorry I forgot to say 要是 in this structure means 'if'.