To answer your first question: the max upside on parks aka "horse power" is not that difficult to figure out, but most would argue it's the least important from a risk/reward standpoint.

I may have put the cart before the horse but I didn’t want to miss the deal.  

Second, it reduces the filtering that could take place between the brokers and you are getting it straight from the horses mouth. 

I have no horse in the race other than caring about BP success.

- beating a dead horse. 

But the horse has been out of the barn for 2 years, don't worry about shutting the door, just deal with it and mitigate and move on. 

Pick a good horse and ride it. 

Let me tell you something..If you keep falling off a horse, some people will climb back on and think "see I don't give up"..

Actually right after I posted this, I did a search and yup, this horse has been thoroughly kicked. 

I don't have a horse in that race as I invest locally in multifamily and also am a realtor here in the Chicago western suburbs, but I think you would be potentially wasting your time on the smaller deals.