After using the 70% formula and deducting the repair cost @ 40k I am at 33k.  

Wait for the right tenants, one month vacant is better than having to go through the whole song and dance 12 months later. 

@Courtney Cottonso in my experience the insurance company has tables and formulas that they use for appraisals.

My question to how ever can help is when wholesaling a property that will be used as a rental for the buyer and not a rehab house what's the formula (I guess you would say) in figuring out the right price to purchase and sell to your end buyer. 

For a new property (once you've met their timeline), lenders use the formula:  net rental income = (75% of rent) - PITI. 

Flip2freedom episode 77http://www.flip2freedom.com/a-3-step-formula-to-a-... - LISTEN TO THIS TODAY!

Or is it some formula you have developed by yourself? 

I was speaking with a local real estate investor that mentioned his quick glance rehabbing formula he uses on houses he doesn't have the time or ability to do an actual walk through on (he does a lot of volumes, and quite a few of his deals in different markets).

I know you want to start out slow, but as I draw up a business plan, I want to be able to account for growth in strategy and formula. 

In my area, a SFH is about 80% the price of a Multi family so double the income/same expenses makes a much better profit formula.