My question is "how do I structure deals with him?"

Also, the $600 lease payment could be structured as a credit against the purchase price.

. #2 covers a catastrophic issue in or out of your control that makes the entire structure uninhabited/uninhabitable for at least a year. 

But if you do not build out further than your existing porch, that should not be a problem, but you should give them a revised drawing. even a second floor addition that follows the existing structure may need to go before zoning because the set backs may have changed since the house was built and would trigger a variance. it doesn't hurt to ask them and ask what they would require, it would show them that you aren't trying to put anything past them.

Basic philosophy is to structure the investment not only for maximum rewards, but also for minimal risk.

im playing with using a structure for purchasing commercial or commercial with rental units that involves an investor putting up the down payment and my side holding the mortgage.

I just wrote an article on this, about how me and my partner structured our rental property buys.

Use it as an equity stretcher in your other deals.Meaning, it becomes part of other deals and traded as if it add value X as part of the consideration.You would structure your offer in other deals as a "must take" in order to increase the perceived value of your offer on the new acquisition property.

The situation is much more complicated if you have a structure on the property that you don't intend to put into service.

I recommend structuring ownership as an LLC with yourself and other members ( partners).