Partnership protection

[Hank Sacco]

I could use some ideas from more experienced investors in how to protect myself in this deal.

My potential partner is closing on a  house,  which he'll own free and clear with insured title but needs funds to rehab.  I would fund the entire renovation (which is about equal to the value of the house as it sits).  We would fix it, sell it and split the profits 50:50.  We will, of course, have a written agreement.   Since he holds title to the house his interest is protected.  To protect myself should I just file a mechanic's lien when the work is finished or file a lis pendens before hand since I don't know the actual amount of the repairs.  Or is there a better way to do this.  By the way, I will personally pay the contractors and suppliers so I control all rehab funds.