To sell a product or service to someone at the same or close to what the product or service will cost you. Hence the person that you are selling to is being given a substantial discount on the normal price. As the term "mates rates" suggests this level of discount is usually only given to mates, or friends, of the person selling the product or service.
Bob: "Hey Johnno, how muchdid you pay for that computer?"
John: "Got it real cheap mate. Trev sold it to me at mates rates."
Term used to describe the pay rate of an employee who is being unfairly exploited by not being payed a legal wage by their employee. Derived from the wage theft scandal surrounding ex Masterchef Australia judge George Colombaris' restaurant empire.
" My new RM is a total cunt"
" Oh shithow come?"
"They have the gall to stick me with George Rates and expect me to live off it!"