One of the surest ways to ruin friendships is to borrow money or do deals together.You also run the risk of offering a "security" which has SEC requirements....Most states the simplest is;- 1 lender buys the property and rehab, they get a security deed, they are a debt lender- you the owner and manager get the warrantee deed.They have no say, just get some interest rate arrangement.   

I always like to try the simplest things first. 

The simplest way is probably an LLC taxed as a partnership. 

In the simplest analysis thats $6000 annually on equity of $75K. 

Cash is the simplest. 

The simplest and fastest way to test interest is probably to list with an agent on MLS.

The simplest way to "take over" the property is to purchase it.

The simplest way I can think of: nine of the owners should give a limited power of attorney to the 10th owner, authorizing that individual to handle the sale of the building on their behalf.

This is increasingly common when you have multiple tenants for longer periods of time or when tenants are moving in and out.The simplest method (for the Landlord or PM) is to keep the deposit in place and return it to all remaining tenants upon termination.

The simplest answer is to buy a quality lease from an attorney that is experienced in real estate.