I looked into DSCR and spoke to a few lenders, but it seems I need to have 2 years of rental property ownership before I can utilize; I'm only approaching my 1st year of renting by the room, so I assume I'd need to wait another year before I can look into DSCR.

Here is what I was told or found out by some of the suggested companies.Safely- Told that they are only accepting new customers who have 20+ short term rentals at this time. 

Loan programs that utilize AirDNA income projections to qualify can also be utilized for cash out refinances (if not currently operated as an AirBNB) although some lenders have a maximum cash in hand of $500k-$1M typically at a lower loan to Value of 65-75% for investment property vacation rentals. 

The way I know is; I send the company a list of my customers and when I get the list back the email addresses and phone numbers are accurate.SInce, it sounds like you have not used this type of service before, I will tell you what to expect for and and every other service provider.If you send any company a list of property owners that you own and you want the company to give you the phone numbers and email addresses this is what you can expect .Send the company 3,000 property addresses - you will receive about 1,000 phone number and 850 email addresses.

You can set up templates to save time and customize them to match your brand.

Beyond that, if it's a multi family, make sure you understand if there is a common utility service you need to put your name on so there is no service disruption. 

In AZ, almost everything is utility scale, so 2.5 acres isn't going to attract much attention from power purchasers or solar developers.

My assumptions based off research is I will be able to deduct 1/2 of all allowable expenses based off the ADU square footage (My understanding of that list below)  1/2 Mortgage Interest (Not principle) 1/2 Utilities 1/2 Property Taxes 1/2 Insurance (assuming I don't have separate ADU insurance)  1/2 general house maintenance (depending on the issue and if it's related to the ADU)  1/2 Depreciation (Home value, not land divided by 27.5)  KEY QUESTION: If my mortgage (PITI) is $5400, and all of those ADU deductions equal $3800 monthly, and my ADU income is $1800 monthly, am I allowed to pay the difference in "deductions" from my real estate business income? 

Operating Expenses:Consider all the costs of running a B&B and event venue—staffing, cleaning, maintenance, utilities, insurance, marketing, and supplies.

It is not just a mortgage and utilities payment each month!