Looked up hotels and I see $350-600 per room per night for 2 adults and 3 kids.

The #1 reason that Landlords fail, according to the American Apartment Owners' Association, is the landlord's failure to manage to the lease.  

You could be "The" STR "guy" for American tourists.

The country is great for lifestyle and I believe most American (and other foreigners) buy for lifestyle.

From an american perspective1.

They highlight the difference between the average home cost and the average home value suggested by the price of large institutional companies such as American Homes 4 Rent and Invitation Homes Inc.I suspect this is nonsense (especially as according to google their price to book ratio is positive). 

Know this:  the #1 reason why landlords fail according to the American Apartment Owners' Association is failure to manage to the lease. 

If he qualifies, create a new lease with all adult occupants (and a sublet provision) and get it signed and place it in a known location.good luck 

In 2022, half of American renters spent over 30% of their income on rent and utilities, the highest percentage ever recorded. 

However, IL landlord/tenant laws are tough and are worth taking a deep dive into if you are going to investLawton, OK - Good opportunity for sure as many mid-American towns like this are prime for investors.