There are some hyphenation questions that fall into a “gray” area.
This is the method I would try when you are in doubt — or maybe when you just want to figure it out.
…sunny breakfast room
First, it is a room. Then, it is a breakfast room. Last, it is a breakfast room that is sunny.
If this works, there is no hyphen.
…large green bug
First, it is a bug. Then, it is a green bug. Last, it is a green bug that is large.
When this works, there is no hyphen.
Some of them are not incredibly clear cut.
…wrongful death claim
First, it is a claim. Then, it is a death claim. Last, it is a death claim that is wrongful.
I, personally, don’t think this one works. It makes more sense to say that it is a “claim” about “wrongful death.” Thus it would be hyphenated: “wrongful-death claim.”
The same with “front-seat passenger.” It is not a “seat passenger” that is “front.” So there is a hyphen.
And, of course, remember that an open compound noun is not hyphenated when it becomes an adjective.
…real estate broker
…high school student
…social security payment
Hope this helps.