Kerr - thank you for helping me - having a second set of "Experienced" eyes looking at an opportunity helps to reduce the "Fear Factor"

DTI, gross income, credit score all play a factor in how much you can borrow.You may want to reach out to @David Ribardo.

Ideally everyone has vacated but if not you should immediately start eviction.  

That would be the ideal target. 

I always use a discount factor of  5%-10% from advertised rents for analyzing the deal to leave room for error/market changes.good luck

And how does my rental income factor in?  

You should use the BP calc, or another one, and factor in all expenses, including PM fees.

That value could go up or down depending on the specific factors of your market.If you apply for a refinance or other loan using your property for collateral, the bank will most likely order a new appraisal and base the loan on the current appraised value.

Septic is not ideal but the lots look plenty big to support it, you just need to make sure that the land perks.

I would wait a bit, market your rental on FB, craigslist and local places to see if you can get a long term tenant in there that will stay for the full year or even longer which would be ideal.