Sweeten the deal
Meaning: to make an offer more attractive, to make a bargain or a business transaction more appealing by adding value to the transaction
Example: The dealer sweetened the deal by throwing in free car washes. He wasn't willing to do anything to sweeten the deal, so I left. She sweetened up the deal with a little extra money.
Example: The dealer sweetened the deal by throwing in free car washes. He wasn't willing to do anything to sweeten the deal, so I left. She sweetened up the deal with a little extra money.