domain sales contract

I was wondering if anyone here has had a similar experience and could lend some advice. This summer I sold a domain (name not important) for $2,400 on Dan with the buyer opting to pay in installments of 12 months X $200. The buyer made the first 4 payments of $200 ($800) without delay. But last...

I was wondering if anyone here has had a similar experience and could lend some advice. This summer I sold a domain (name not important) for $2,400 on Dan with the buyer opting to pay in installments of 12 months X $200. The buyer made the first 4 payments of $200 ($800) without delay. But last...