I want to create a standard and add or subtract other duties as they arise.

But, figure out that true value, figure out what sprucing up is needed, subtract off what your buyers want for a discount (typically 30%, but some may want less), subtract off your cut, subtract off a bit more to give you some negotiating room, and make that offer to the bank.

The EMD will then be subtracted from what you need to bring to closing for example, if you're putting 20K down, you only need 16.5K at closing because the other $3,500 will be in escrow to be applied at closing.

Calculate the home equity available: Subtract the amount you owe on your current home (the mortgage balance) from its current market value.

You need to take your tax basis (what you paid for it plus those improvements) and subtract that from what your net sale will be.  

Subtract costs (only a few will make up 90%.

Debt service of at least $6k/yr subtracted from the $9700, leaves $3700.

Subtracting out another $3000 for water, leaved $18,000 to pay the loan, or $1,500 per month.

They have it in the operating expenses and it is included in the net income...Should I subtract the interest out of the operating expenses then?

End result is your max value of the house; from that you subtract repairs to get to max offer amount.