Re: reach a turnover in its contacts
No no! You need to separate the "turnover" phrase from the "making change" sections in your mind!
Making change does indeed mean to give to the customer the difference between what the customer gave you in cash and the cost of the product. I give you a $20 bill, and my item costs $5.29 with tax, and you give me back $14.71. That has nothing to do with the "turnover"phrase earier.
I'm not a teacher, but I write for a living. Please don't ask me about 2nd conditionals, but I'm a safe bet for what reads well in (American) English.