Self employed tenant screening

[Debasish Bhattacharjee]

I am currently searching for tenant for my rental home in Tracy, California. I have two applicant applied both of them are self employed. I am using zillow background check and verified both of their BG is clear, have gone through their credit. 

First couple has excellent credit - both has above 815+, had a home purchased in 1990 and credit doesn't show up with any mortgage which I assumed they have paid off by now. I have run tax accessor property check and they were on time for last 15 years. Rent to income ratio is 6.4X. Rental is 5bed 3 bath single family and rent is ~$3K, and their income is ~20k/ month. They are 100% on time, no eviction, current auto debt is 42K, no bankruptcy , no collection, 0% credit utilization, longest credit length is 31+ years. They run a child care in their own house which they need to expand. I looked at the property they own which 2 bed 1 bath and they mentioned they want to extend their business and thats why they are relocating to 5bed 3 bath home. I am wondering how could even they manage 2 bed  1 bath and now they are moving to 5 bed 3 bath. Is it resonable? Should I take care of that or not?

Second couple doesn't have any home, but for last 10 years they have been renting out. They are also self-employed and their rent-to-income ratio is ~4X (13.5K). Truck driver and self employed. One person has credit 720+, second applicant's name is there but no info. 100% on time payment, but credit card utilization is 32%, has 100K debt (auto + student loan)

I have informed them to provide 1) 2 years 1099, 2) 1 year bank statement (personal + business), 3) 1040 tax return for last two years, 4) if they have any profit & lost statement. This part I don't know who provide? Is this a third party company always provide for self employed business?

Is there also a way to check the status of the company in California business registry?

This is my second time hiring / screening for tenant for self employed.

I do have third applicant with w2 with 700+ credit, 6 years employment in Kaiser, and 6 years rental history but with rent to earn ratio is 3.2X.

Whom should I choose and all three of them applied with-in an hour after listing.