Dolce, if you are not interested, then what you are doing is right. But Desert Eyes does have a point.
So maybe mention a having a boyfriend or tell him you are interested in someone? This implies to him that you consider him more of a friend. Then wait a while and mention the payment thing again. If he does take payment, then it may mean that he liked you, but if he still doesnt take payment, then he may just be a really nice person. Im not saying this will definately work, or that if he still doesn't take payment he doesnt like you, but its what i would do.

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