Additionally, their property management team takes care of tenant screenings and maintenance.

The Father applicant responded by offering 6 months of rent upfront (even the entire year) and is willing to provide 3 months rent of refundable security deposit for the additional dog risk.

Should I hire a contractor to add an additional meter that separates the ADU from the main house or charged another fixed amount for the main house as well.

This only works on flips and BRRRRs, otherwise you won't be able to pay off that much debt unless you have other sources of income coming in.This is what I did on my last deal in TX. 

Additionally, incorporating automated data entry software can greatly enhance the efficiency of these accounting systems.

I have a house, no kids, good income, no debt.

I had one owner who was stuck with only $700 of income for 4 months because it was the last remaining room lease before we could rent the house to a single lease holder.  

Also, focus on 2 years of job/income stability.Class D Properties:Cashflow vs Appreciation: Typically, all cashflow with little, maybe even negative, relative rent & value appreciationVacancy Est: 20%+ should be used to cover nonpayment, evictions & damages.Tenant Pool: majority will have FICO scores under 560, little to no good tradelines, lots of collections & chargeoffs, recent evictions.

If not, what would the additional cost to insure your building with the new type of Tenant. 

I would also prioritize trying to replace your regular 9-5 job and then gradually increasing your income with more experience.