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 used Satori Software for processing, a postcard address printer.

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).

Brand AwarenessAlthough, number 3 I could argue is more important for future years and not so much right now as I'd more concerned with further cementing our business structure, working out systems in all areas of the construction, reconstruction, and rental arenas.  

@Michael Seeker These "condos" are exactly the same structure as mine. 

I'd like to find some software that will allow me to enter my expenses and then sort out how much I've spent per unit, per contractor, per category, etc,. etc.

To my knowledge, lease options if structured properly are bona fide legal and you won't run into problems with DBPR, etc.