Multiply that by 1.25 and then add it to material costs.

Secondly, how disciplined are you to not "waste" your savings while they are sitting there doing nothing, instead of multiplying them SOMEHOW?

. / 3 =  640 for a rent multiplier  IE most landlords want 3 times rent as your gross income..

Stepped away for a bit because I got real busy and come back to an avalanche of responses!

It is important to not over leverage, but having a leverage multiplier to the number of units you have provides protection from your scenario.  

After multiplying by .95 and .55 for vacancies and expenses it's roughly $2600 a month but if it sells for $620,000 then even a 30 year mortgage at like 4% with 20% down doesn't even break even.

What some savvy investors would do is calculate the difference in monthly payment between a traditional lender's rate and hard money, multiply by the number of months they will be in the financing, and compare that number to the cost of repairs.If it's just an oven, it'll almost always be the case that it's better to throw an oven in to check the box for the traditional lender.

But remember all it takes is one snowflake to hit the mountain slopes to create an avalanche, and you never know which snowflake it will be. 

It allows you to create equity and multiply that seed money. 

National average appreciation is 4%, and multiply that my your leverage factor (4x on a 75% LTV), your true ROI will be 16% + cashflow.