If you are using closed/open cell spray foam, you need to make certain the bricks are able to breath and dry - otherwise they will spall - so normally you do not want to apply the foam directly to the brick.If the building is structural brick, then there may be an internal framing for walls, but more likely there will be furring strips attached directly to the brick.  

We receive it and transmit it; we find it and lose it; we store it and leak it; we conserve it and spend it; we are breathe it in and we breathe it out; we hold it in and we let it go; we are more of who we are when we have a lot of it and less than we can be when we have only a little.

I prefer to go directly to the smaller boutique turnkey companies that live and breath the market I am interested in.

Id love to see one, but I wouldnt hold my breath hoping for one.  

Check out stuff from Eric Thomas (Google "as bad as you want to breathe") and anything else that gets you pumped.In short "keep up the fight"Let me know how I can help.

Initially, I would just insulate the attic (such that the air handlers for the heat pumps were in the conditioned space) and defer the decision.If you can get the building in the 165 - 180K range, then you have breathing room to properly finish the half-done HVAC conversion, fill at least three of the units and then start the efficiency upgrades to the building envelope as you turnover units. 

I live and breathe RE and would like to eventually move to the other side of the table as an investor. 

Once you have breathing room look for Cashflow.

Best advice is to take a step back, take a deep breath and honestly ask yourself if you are scared of doing this.

@Christian Shope,Close your eyes, take a deep breath and go to your happy place.