Jurisdiction and Venue: Which State Do I File the Small Claims Suit for Collections in Different State

My question involves court procedures for the state of: Iowa, Illinois, and Colorado.
I have two loans to a person.

1. 8k to a person to start a business. We signed papers in IL for the repayment of that loan but did not have a witnessed. The individual has not paid much of anything back but all payments have been recorded on my end.
2. 3.5k of past rent and some charges on a credit card the person had permission to use one time but instead set up auto payments.

This all transpired in IL.

The defendant has agreed to sign new agreements for monthly installments and they will be witnessed by a notary next week in Colorado. The problem is I now live in Iowa, and the defendant now lives in Colorado. I will be signing these new agreements in Colorado. When the defendant defaults on these agreements (which I'm confident he will do), where do I take him to court? Colorado or Iowa?

And if I win the suit, will Small Claims court allow for wage garnishment?

Thanks in advance for your advise!

Jurisdiction and Venue: Which State Do I File the Small Claims Suit for Collections in Different State