Looking to buy first commercial building

[Wills Manning]

I am looking at buying my shop (It is a building and a barn on a .4 acre property with a fence surrounding). I am one of the 3 renters (I have a landscaping business). Total rents are 2050, taxes are roughly 3300, and the Landlord wants 190k for it. Other than that we (as renters) are responsible for all utilities, snow removal and lawn care. So the landlord is resposible for upkeep on the buildings (maintenance and cap ex) and the taxes. The shop is also located in a tif district. I am having trouble running a report on this property as I do not know what assumption I should put in (for vacancy and maintenance) and I only have experience with multi family buildings. I have a few questions: How do you value a commercial property based off sqft? What do I need to know if I am planning on buying this property?