credit partners

when using peoples credit to either re fi or purchase a house what all do i need to do to protect myself? say i buy a house at 60% value and my credit partner goes back on me and doesnt let me have the property? how do i protect myself for something like this? what kind of paperwork at closing do i need to do to get that property? do i just have them deed it over at closing and have them sign something before the actuall closing saying this is what they have agreed to do?

also how can i show that my credit partner is secure? im dealing with their credit, how do i make them feel secure?

My dad bought a property a few years ago and this guy from the neighborhood keep saying it was his property. (I guess his aunt owned it and died and he thought she left it to him). My dad would put for sale or for lease signs in the yard and this guy would pull them up. One day the guy turned up dead. The moral is that in real estate if these credit partners try something funny they need to make sure they are prayed up because they may wind up dead.