From my experience, 50% of the net price to the brand up front is common practice when making an OEM product you can`t sell if the brand fails to pay.

Large brands / retailers have different negotiated terms. For some, like Wal-mart, they want to use their logistics machine to it`s fullest and they buy FOB factory (Ex-Works). Other brands / retailers, usually wanting to work on factory money, will want extended terms and they pay for the privilege.

John