I have a client who wants to purchase an artwork. After three weeks of questioning about my artwork finally he is convinced to buy it. I have offered him discount after his multiple request and 15 days of payment time in invoice. Now he is asking for payment extension. I think that he might ask for extension again! I'm actually tired of him because he is not paying and wasting my time. How to deal with it? Your expert opinions are appreciated.
I have not mentioned late fee or due date interest fee in the invoice.