This will be a true turnkey investment, so any insights there as well are greatly appreciated!

I think there are two maybe 3 ways to look at this in my mind.  1) you go into it and bring it all up to modern standards but using that old charm to basically take what is there bring it up to modern standards and rent it out essentially I'm thinking cocktail bar or something trendy like that.2) most banks are on really good centrally located real estate if this is true, then I'd consider it for the dirt, plan to scrape the lot and go vertical with whatever the highest and best use is.3) a kind of combo of the two, if the lot is in a good location and its doable, pull the vaults or other "character pieces" out of the building, scrape the lot, and build whatever is best suited for the site there, but incorporate those historical pieces into the final designs.Is the site near a major retail area? 

Is the old adage that landscaping doesn't get any ROI in a middle-class market still true?

True!  

Also, for the experienced BRRRR folks out there, are you holding true to the 50% Rule on Cash Flow on each project? 

Very True.

In your experience do those rental comps hold true if you go North of Addison (specifically Irving & Kedzie area).

Very true and we were kind of thinking about that 3 year time span as well.

This is true.

Also make sure you understand everything about adding an ADU including value of the ADYPU, financing, impact from rent control, duration between initial expense and initial income, true cash flow (know the 50% rule, at 50% rent ratio initial property tax will be near 20% of income)- educate.