pounds or pound, quid or quids

[Unregistered]

I am really confused, could you explain how we talk about money? do we use singular or plural?

[calinative]

I am guessing at this question for you according to how American money is used in American English. I don't know if this applies to the pound or quid.

Generally, use "dollar" only if an item cost one dollar (singular) and "dollars" for items that cost two dollars or more.

Examples:
The house costs half a million dollars.
I gave her a dollar yesterday.
He asked for ten dollars.
I paid for the TV with 25 dollars!
Can I have a dollar?
The painting is worth 2 million dollars.

However, there is an exception to the rule. If the price is used as an adjective in the sentence, you always use singular.

Examples:
That is a half-million-dollar home.
He gave her a 2,000-dollar diamond ring.
It's a ten-dollar deal.
Be careful, that's a twenty-five-dollar TV!
The 2-million-dollar painting will visit all the major museums.