@Bruce Lynn is pretty close, and maybe right on the money with some areas/operators. 20-30% is pretty common.

Let's look at the law.Telephone Consumer Protection Act Of 1991 (or commonly referred to as the TCPA)While mass texting is by no means illegal, it is heavily restricted.

Any other information about what you see from tenants commonly would be helpful.Thanks

The other much more common occurrence is that the addition was done without permits (this is an actual physical condition issue).If the permit was pulled but not documented then it is usually resolved by following up with the permitting authority, and then providing the documentation to the County Assessor etc so they can add it to the tax bill.

Collecting rent in full and on time is the biggest, most common challenge, but there are so many more!

Hitting a "cash ceiling" is a common occurrence for property investors looking to scale and there are a few different ways to power through it.  

Now I’m curious though, is running credit and background on all partners, even if they aren’t bringing money to the deal a common practice with HMLs?

Better management and site layout, moving a few tenants around and creating more efficient common areas to increase the rentable square footage.

For utilities, I was hoping tenants can pay their own utilities but feel free let me know if that is not at all common in Chicago (will add water to my calculations). 

While it may be conservative, having a big cushion of available capital has allowed me to get through many sticky situations that were not foreseen going in (main stack and sewer lines being the most common).