You will have formation costs, earnest deposits, legal bills, due diligence costs, etc that will likely all come out of your pocket initially.  

Deposit a lot of money at a bank you will do business with in Illinois.  

They may be receiving rent payments casually in cash or depositing them into their personal account where everything is mixed together and hard to find the dates and amounts of payments to provide you.

I require a $1,000 security deposit, no exceptions and I let them know they will be paying all utilities, mowing the lawn, keeping up the landscaping and cleaning the gutter. 

If some applicants fall below your requirements, then everyone would be considered "conditional," you can raise the security deposit to mitigate your risk of someone breaking up or defaulting. 

Deposit the checkSometimes the banker will want a copy of the POA for their records, which we'll gladly provide.

I do not like this as obviously if a business account is only accumulating rent from 1 property, it wouldn't accrue the cash in each as quickly as it would if all of the rents were funneled into one account.. and it makes paying the bills a bit of a pain on each of the properties as I am having things done to the properties, lawn care, etc.. constantly has me making owner investment deposits into each to cover initial expenses associated with the properties.. etc. 

An STR will look every bit as good as it did when it started - because it has to.Not only that but it is much easier for property managers to get repairs reimbursed when a guest damages something as an STR as opposed to when a long term renter moves out and outside of the security deposit, good luck. 

You can even sweeten the pot by telling them they don't have to clean, and you will hand them their deposit on the day of move-out after a 10-minute inspection to verify there are no damages. 

If not, the contract can be terminated and you would get your deposit back.