I will say the property needs structural support repair so I added in 8k for that plus cosmetics for a 45k rehab budget.

He has a 400k HELOC ready to use..Question: What is the best way to structure this??

Saying that many people do deals this way may be true, but it doesn't mean it's the best course of action or most risk averse for someone who it sounds like is still learning the process and doesn't have the basic structure yet figured out.

the way im structuring things is everything is tied into a security deposit.

@Subbie Kaur: Thanks for your input and my strategy is to buy low and sell High, with that said I am in the beginning stages of investing and have a limited knowledge of the inner workings of Taxation Corporation structure so on and so on and I'm sure there will be some bumps along the way but to make a long story short my strategy is simple to make money honestly and legally regardless the end of the day make money

Typically (in most states / housing markets) market value (what you pay for the property) is usually less than what it would cost to rebuild the structure (replacement cost).

It depends on the structure of the firm you choose. 

Landlord rules are you install it as a permanent structure its mine (insulated and walled the garage) temporary it's yours (huge wall storage, which is too difficult to move he can keep lol)Would I be considered a dirty tenant I don't think so.

That is the common insurance structure we use when rehabbing properties here in Connecticut.

In regards to the deal I can't tell you how to structure a partnership.