Everything is negotiable, even as-is properties, especially with major unknown structural and mechanical issues.  

(emphasis mine).  

But the same could be said of an auto mechanic.

Hi All - I have experience buying and operating individual rental properties but am now attempting to figure out the mechanics of how I can syndicate a larger multi-family deal.  

There is no such thing as a 1031 exchange mechanism.

This was an auto body shop and paint booth for over 20 years and not used for mechanical work much at all. 

The exact mechanics depend on how your business is structured, but there is no "rent" involved either way.

I have full time mechanical engineering career that lets us save some money every month.

You can get this by involving other investors, but if you're trying to maintain 100% ownership of all your properties, you have to have some money to bring to the table to start the BRRRR cycle or whatever other mechanism you are using to make profit and cash flow in real estate. 

Do you have a break down on how much each mechanical system ended up costing you etc?