50% t/t(电汇,你可改成其他付款方式) down-payment after contract signed,50% T/T after acceptance with Buyer acceptance-form；
50%合同签订后预付,50%在验收并由买方出具验收报告后付；
我稍改了一下,因为这是比较严禁的说法,有时货到了,但是不合格对方要求付款,所以加上了出具验收报告；
The Seller promised to ship the goods（你们的货,可改） after receiving advance payment,7 days net；
All payment after being invoiced by HongKong invoice;
或楼上的简洁说法