I'm seriously looking at a flip in the historic West End Atlanta area but I'm getting conflicting data and I need some help sorting things out. 

Have you check Resiclub data about inventory ?

If it takes 6months to evict vs 1 with each eviction you lose more rent.Appreciation is harder, but take a data driven approach.

Maybe bring a few example properties to show what you are thinking of buying.Also, many cities/towns/counties have the data for each property online in a searchable database.

Then I subscribed to AirDNA to get location specific data.

It’s totally free.This report gives you that insider knowledge and data.

Those figures are based on market data and info I received from a property manager who toured the property.

See below output with a few thoughts:- Would need a few more data points to be precise (rehab estimate, duration estimate, property taxes, insurance, utilities, HOA, maintenance, etc.).- Assuming a 12% HML with a 3% origination fee held for 4 months, with a 30-year cash out refinance at 70% LTV and 7% interest rate, where the property stabilizes two months after refinancing (6 months after purchasing), you would (i) nearly breakeven on the cash out refinance and would generate $455 in monthly net cash flow in year 1, increasing annually, assuming you rent for $7,000 in year 1 and increase rent 4% YoY.- See below and let me know if you would like me to send you a copy.

Third, I'd like to know what data I need to collect in order to write this off on taxes.

If you do not have these two steps than you will never get the unit filled.The ProblemBelow I included a chart and the raw data to help you understand our concern.