see the colour of someone's moneysee the colour of (someone's) money
to make sure that someone can pay for something before you let them have it.
I want to see the colour of his money before I say the car's his.
see the color of (one's) money
To view the money that one will pay with in order to verify that they have it. Sure I trust you—but I still want to see the color of your money so I know you're good for it.
see the colour of someone's money
receive some evidence of forthcoming payment from a person.