If you were in the same boat and all of a sudden your hard earned cash was liquidated and the guy walks away with the assets of the business I do not think you would be very happyMoney is king in this economy so split everything 50 / 50 You would not be able to start the business without his supportYou also need to put a value on your time was sweat equity so there s no arguments later to say we did not contributePut into the contract how many unpaid hours you are putting in each month to equal his cash contributionYour input into the business must equal or be more than the money he is putting upwrite down all the what ifs and have an exit strategyput into the contract it is a difficult trading economy and that if it does sour it will not harm your business relationshipwrite good and bad things down that you would be unhappy with and ask him to do the samethis way everything is in the open before you start when you can still discuss things openly
I hate to break it to you but when someone invests in a start up company of any kind the one who puts more cash in usually winds up retaining more ownership in the event of the company folding or liquidating. You should spend the money on an attorney to set this up for you. If this is a company set up where your partner is hoping to participate in the publishing as well as the masters then you should look into making a time limit on his participation rather than co-ownership in perpetuity. Seriously though - spend the money - hire an entertainment lawyer with music business experience.