It is likely advisable to have a written agreement that addresses all sorts of possible issues that could arise in this situation including with regard to the loan and any mortgage interest deductions, splitting of expenses, splitting of profits, tax reporting, what is to happen in the event of disagreement, any rules about rehabbing such as particular types of materials to be used or types of projects (can he choose the cheapest and ugliest materials, consider that has having rehabbed it, and then takes a split of the profits still at 50%?)

I told her that's between them, and she is responsible for rent payments and damage as long as she is on the lease.Recently she sent this:"Can he legally change the locks on the house without giving me a key?"  

I am no legal expert but how can he sue you if you re not the actual owner?

He has a real estate LLC, can he lending out using his real estate LLC as an lender?  

But how can he possibly stay in business?!

•What type of advice can he give you just starting out?

What if one person wants to leave the partnership - under what terms can he buy the other out?

Can he "pawn" a car?

If you dont know what you are doing you really need to connect with a professional agent who knows EXACTLY what they are doing and that can be hard to find.I know a big investor in my area who gets the newest agents he can...  he

Just a couple of thoughts; Can he do more than one lot at a time to spread the costs over the lots, or can you use bigger equipment that would make the work faster.