70% rule and my math...please help (lol)

[Carl Gorson]

A little help w/the 70% rule calculator and my math please. ARV 159K. Rehab Cost 60K. No extra profit needed. After hitting the calculation bar it gave me an Est. Purchase Price of $51,300. Now , ARV-RC-EPP=$47,700. I have read in the blogs that the 70% rule accounts for approximately 13% of your ARV for profit. So 13% of 159K =$20,670. Bear with me please . $47,700-$20,670=$27,030. MY QUESTION. Is the 70% rule calculator giving me a $27,030 Just In Case (JIC) buffer? Thats aprox. 45% of my entire rehab budget . Is that excessive or is that what I should anticipate ?