bottom dollar

But I know the value of money, I do, and you may bet your bottom dollar that I'll make things hum.

I would give my bottom dollar to be able to answer the question.

I'm not much on poetry—but you can bet your bottom dollar it's flowing all right.

If you see two women together, you may bet your bottom dollar they are discussing their own or their friends' clothes.

Truly I'd ha' given my bottom dollar to be a settin' under that old oak that we had to hum, an' a breeze a-stirrin' the branches.