Just a discussion I had with someone about possessives,or 'quasi possessives' as it turns out. Just some assurance/opinions sought that all below are correctly written:

Your money's worth.
My money's worth.
Our moneys' worth.
Their moneys' worth.

'Monies worth' would be wrong in all cases.

I am NO expert, Martin, but I truly believe (before I go and look in my Grammer teacher's Bible) that those are correct. It is quite a complex thing as Money is a non countable noun, to add to the complexity. Hmmmm. I hope there is a Grammar expert here (probably a non native speaker) who can help.
Later
No I am wrong
The non countable noun-ness of 'Money' means it is "Their money's worth." "Our Money's worth." (I think)
!@#$%^ Help^&*!!!

Moneys is sometimes used in the sense of specific sums of money or payments, usually in more or less official contexts (The Treasurer shall keep a record of all moneys received). Once upon a time monies was an acceptable variant, but Fowler (writing as long ago as 1926) calls this form "obsolescent" and I think most of us nowadays would see it as simply wrong.

However, I certainly don't think moneys is right for the total amount of money held by several people. We would surely say A night at the opera will cost all our money or all the money we've got, and not all our moneys. So it must be our money's worth. It just seems confusing because the possessive 's leads us to think we may be dealing with a plural when we're not.

TT that's exactly what I meant! Thanks!

'Money's worth' in all cases then. Monies shouldn't really be used at all. I was sure about the first two but unsure about the others.

Thank you Ren & TT. I knew this would be the right place to ask.

I don't think so. We're dealing with two different things here.

First is the contraction. When I see "money's worth" it's not a possessive. The complete phrase is "money is worth" The 'is' is contracted to ''s'. Like when we make 'would not' into wouldn't' or 'the lion is vicious' into 'the lion's vicious'.

"Money" can have possessives like 'the money's musty smell' or 'the money's damaging effect'. These are rarely seen or heard since we don't usually assign inanimate objects with the ability to 'possess.'

I'll try to find better examples.

Does this clarify it?

AHSGE Language Study Guide
Apostrophes
An apostrophe is used to form a possessive or a contraction. Check for the following common apostrophe errors. The bracketed parenthetical demonstrates the correct use.

Possessive Nouns

1. Singular possessive nouns. Use 's to show that a singular noun is possessive [the defendant's motion]. You can apply this rule even when the singular noun already ends in "s" (Charles's costume) though many writers add only the apostrophe [Charles' shoes].

2. Plural possessive nouns not ending in "s." Use 's to show that a plural noun not ending in "s" is possessive [the children's toy].

3. Plural possessive nouns ending in "s." Add only an apostrophe to make plural nouns possessive [the boys' game].

4. Nouns that are not possessive. Do not add an apostrophe to a noun that is not possessive [the teachers (not teacher's or teachers') have claimed; the Joneses (not Jones' or Jones's) did not attend].

Possessive Personal Pronouns vs. Contractions

Apostrophe errors with possessive personal pronouns are common because possessive personal pronouns indicate possession and we are used to using apostrophes to indicate possession. Also possessive personal pronouns are easily confused with contractions. Here are the basic rules:

5. Possessive personal pronouns. Do not add an apostrophe to a possessive pronoun [the problem is hers (not her's); the corporation must disclose its (not it's) assets.]

6. Contractions. Do use an apostrophe in a contraction (it's time to go; you're the one).

* Watch especially for errors in using "it's" or "its." Remember that "it's" means "it is" and "its" indicates ownership. Confusing these two words is the most common apostrophe error.

I think it is more confusing. My understanding of the term "money's worth" is value for money, so if I was paying a pound for an item was I getting good value for my pound, in other words " getting my money's worth". Is it a term used in the US? It is pretty commonly used here.