Zipcodes don't work too well as they are large and contain many variable areas.

I may not be well-versed in Michigan's laws, but if the lease you both signed contains that language, then you are bound to adhere to it.

On a single SF investment many newbies use a spreadsheet, which is fine and containable. 

Has anyone ever used conex / shipping containers as mini storage?

In that case, you might want to engage the city to encourage better use of trash containers with lids, talk with the hauling company, etc.

However, it seems I can buy a shipping container of vinyl plank flooring direct from China at a significant discount.

I'd also send them the manual for whatever unit you have which should contain the recommended operating temperatures (and min and max).Edited to add it also depends if they are normally hot or cold and how they are dressed.

It contains hundreds of files such as ebooks, checklists and spreadsheets for real estate investors: https://www.biggerpockets.com/filesGood luck investing. 

My assumption is that the asking price already contains a $5-10K "finders fee".  

It contains 9,328 square feet of retail space 5 tenants.