I would add up the rent missed subtract any deposit not already refunded and subtract the amount she gave you  ($645) and give here any difference if any is left. 

According to RealtyTrac and the National Association of Realtors, the average Fix & Flip takes 6 months, has a gross profit of $67,000 (before rehab costs are subtracted) and has a Net Profit of $15,000 after all expenses are accounted for.

Everything else is derived or subtracted from that number. 

@Jack B. using the numbers that you recently posted (I'm assuming they are the property you are considering, not the sold comp), I would take the $4300 rent, subtract the $500/mo utilities, subtract $800/mo for reserves, ($600 is too low, in my opinion) and $600/mo. minimum cashflow, so I'm left with $2400/mo.

With a MTM, it gives me so much more flexibility in potentially giving a 30-Day Notice to adjust rents, add/subtract lease terms, and/or weed out problem tenants.

True, the lawn is actually close to half an acre, the lot is half an acre so subtract the house and the driveway from that and most of it is grass.

Subtract this from $700, and you're at $550.00So just to give the message that rents would increase, I would do it in $25 dollar increments, and get to $550 in two to three years.

Once you close you can give a 30/60 day notice as to what you want to change add or subtract from the original lease agreement.

In order to calculate the values you highlighted, do the following:Purchase Cap Rate is calculated by dividing Net Operating Income (NOI) over the Purchase Price.NOI Is calculated by subtracting all operating expenses from operating income. 

I then subtracted that amount from the 850 and then subtracted 50% So, $850-$430 = $420 x 50% = $210.