Whatever makes you and your investor happy after the deal is done. If it was me I would expect to give up 10% - 30% depending on the size of the investment and

Whatever makes you and your investor happy after the deal is done. If it was me I would expect to give up 10% - 30% depending on the size of the investment and who's making it. Pay a lot more attention to issues of control and the other deal terms. They will help or hurt you a lot more than having a little more or less stock.