In our area it's like $1 to $1.15/sf. for smaller houses, but it slopes down as you get bigger... so the big house might be a $0.90/sf or something.Heading for the finish line, you can now take your approximate rental income based on the $/sf figure you just found, and subtract your "all in" expense to determine your pro forma monthly cash flow for the property.  

By renting it out for 1100 a unit and subtracting all expenses such as maintenance, capX,utilities, taxes, and Insurence and the 30 year mortgage it would cash flow 564 dollars a month which is a coc return of 85%.The other option I am considering is not financing it and opening up a HELOC that I can use to purchase more deals.

IF your assumptions are correct, you should be able to get a HELOC up to ~80% CLTV.Which means you take the value of $320k x 0.80 = $256,000.Then you take that number and subtract out your first mortgage ($256,000 - 1st mortgage)This will give you about how much HELOC you would be eligible for.

And if worst comes to worst, compare it to Single Family in such a way: - find Single Family with same square feet, number of bedrooms, bathrooms- find Single Family that has been renovated/rehabbed (I am assuming you will be rehabbing your duplex)- then subtract 10%-20% since you are offering a duplex instead of a Single Family in the same area. 

The last statement I got had Their net income at -$10, without subtracting any of their management fees.

Do the math on the sprinkler gpm subtract from total equals tenant usage, determine if excessive ...I billed a tenant for the 3rd quarter, took an average with the past 4 quarters billed the difference, as the lease allows.

For exchange two - To defer all tax you must purchase at least $1.3 ish (subtract closing costs) using all of the $460K of cash.If you want to combine those exchanges you're absolutely right you have to meet the 45 and 180 day deadines for both exchanges. 

Keep in mind, that if you have to knock down a property, you have to subtract the cost to do so.

Or if I am using my own cash for part of the rehab, would I enter that cash amount in the cash field and then fill out the other parts subtracting the amount I would pay in cash?

So if you're using AirDNA's projected revenue then you will need to project cleaning expenses to subtract out.Also note that AirDNA's data is based on trailing data for the last year.