Probably not.
No, the phrase "top of the line" is not hyphenated.
It should be hyphenated.
Yes, end-product is hyphenated. It is a noun and treated as one word which is hyphenated.
No.
No, the phrase "thank you note" is typically not hyphenated when used in a sentence.
The noun phrase 'four week vacation' does not need to be hyphenated.
Yes, one-on-one is hyphenated. I don't know why, exactly. It just is.
Yes and no. The out-of-plumb wall should be hyphenated while the wall was out of plumb should not.
No
Yes, back-to-school is hyphenated when used as an adjective phrase before a noun, such as "back-to-school shopping."
The term "bought out" is not hyphenated when used as a verb phrase, as in "They bought out the competition." However, when used as an adjective, such as in "the bought-out company," it is hyphenated. Context determines whether to use a hyphen or not.
Point of sale is a business term used to describe when the retail transaction is complete. The phrase "point of sale" is not hyphenated.