If you have a job you're not planning to quit anytime soon and you don't need a quick paycheck to suport your lifetime I think BRRR is definitely the way to go. 

Over time, I plan to refinance to help create even more cash flow, and with time, rents will most likely increase.

If you prorate do ask them when they plan to stay until and are they staying until the end of the month or do they want to give you a date now that they will leave because my guess is they aren't leaving on day 20.

I have a plan to buy my entire block in the country.

Your cash value grows tax-free (with proper planning), providing you with an ever-increasing resource to fund your real estate ventures!

IMO it would be worth paying a local attorney who performs evictions in the area the property is located for an hour of time to put a plan together to make sure you don't accidently do anything out of bounds.

I’m closing on a duplex I plan to live in one side and keep one of the tenants on the other side .

It's what I plan to start with and it's highly recommended for newbies like us. 

Focusing on what makes sense for you and your business plan while factoring in market conditions will land you good buys.

If you plan to buy cheap low cost properties and primarily seek cash flow, then you can use simple ROI/CoC formulas.