If you were looking to use the rental income from your roommates to help you qualify then you would need claim it. 

The other good news is you ca use the rents of the other units as income to qualify so you can essentially qualify for a higher home price.That sets up your next investment property as you move out its now a 2-4 unit with multiple doors bringing in more income. 

I'm going to run some details by you and I'd like all of you who feel you are qualified to advise me so I can learn how to properly analyze these deals and be more cognizant of potential pitfalls/mistakes:So, I found this property off market in a Chicago real estate investment group.

Will this property qualify for all the tax benefits of STR?

Also, a great QI (Qualified Intermediary) is @Dave Foster.

All Contractors are subject to the lender’s determination that the contractors are qualified and experienced, have all appropriate credentials required by the state, are financially able to perform the duties necessary to complete the renovation work in a timely manner, and agree to indemnify the borrower for all property losses or damages caused by its employees or subcontractors.Multiple Specialized Contractors:Ø Since this is a limited repair/renovation program, no General Contractor is required.

I'm not familiar with non qualified mortgages, I'd generally assume the less mainstream/vanilla the borrower, the higher the costs and rates, why would non QM instead be lower costs?   

The best thing to do is have a conversation with a broker or lender (or a few brokers or lenders), see who you like working with and get a rough idea of how much you would qualify for based on verbal information. 

However, she wants you to qualify him based on her record, even though she is not living there.

A well-qualified homebuyer familiar with his local market should beat the pants off of an institutional investor any day of the week.