What are the steps I should take to get a solid estimate for ARV and rehab cost.

Ive estimated I can add about 50k on the low end based on comps.

At this price we are looking at (what we can estimate) monthly costs of about $3200 (mortgage, electric, gas, PMI, taxes/insurance).Our concern is that renting it out will not bring in enough throughout the year to cover the 40k cost to own and operate it.

So if its an 8% annual return and the operators are depreciating the assets and use cost segregation, I am curious if anyone has estimates for passive losses on a typical project? 

Just as important, Steve is only asking 125k for the property, while zillow and redfin estimate the property's worth at 170k, this is worth double checking with local realtors but I can guarantee 125k is far below market value.

From those numbers, 3 of us and my girlfriend will be living in the house, so say 1800/4 + utilities estimate, we would come out to around 500/month each if we split the costs evenly.

So, apart from estimating your price by checking similar properties in the area, make sure that you also factor in all of your expenses such as appliances, utilities and taxes when figuring out how much rent to charge.

I walked through and estimated 28k in rehab.

I'm estimating $500 in cash flow at that point. 3.

You have to make your best estimated guess on what development costs are going to be and do you best to stick to those numbers.