The next step after a pre-qualification is to actually get pre-approved where a lender has run your credit, verified your income and verified your down payment.There are several loan  programs that you can finance a home with high leverage with just a 35 to 5% down payment.

TLO also expects you to own the home along with the other qualifications.

I didn't say anything about showing documentation, the script will do, you cannot question medical authority or make unreasonable demands like a doctor's qualification or their place of practice. 

When we moved to a new state for my husband's work, we also rented way below qualifications as we planned to research the area and buy something we could turn into investment property when we left, but we rented short-term in an apartment complex, didn't bother a single-family landlord. 

You should be able to get a pre-qualification letter or even term sheet through filling out an application and credit authorization and briefly chatting with a DSCR lender to see where you stand. 

Should I have them do the same application process and ensure all qualifications are met as I did with the current tenant? 

if that's the case, you may have some small level of qualification that you combine with a co-signer to get yourself into a house hack using a low down payment option. 

If it's a larger organization, feel free to inquire about their staff qualifications.2.

You could attempt to switch your passive income to active, but then you lose write off's, and that's a different decision altogether.I'm a 401k administrator, and when we have clients with passive income (who are often RE investors), we need to go with a non-qualifed option instead of a qualified option (401k, profit sharing, etc.).  

After you figure in the expenses not included in PITI (Vacancy, Repairs, Capex, Etc), your rental income, in terms of qualification, is going to be lower than you expect.