confirming offer price

[Kim Knaust]

Example - $103,000 ARV

ARV minus the following:

$4,120:   4% acquisition costs & holding costs (2% each)

$6,180:   6% real estate fee

$30,000:  avg rehab cost

$30,000:  avg profit

$32,700 offer price

However, the teach said to use .67-.72 of ARV if I'm a cash buyer to get the offer price and that would between $69,000 - $74,000, which is way off of the $32,700 above. 

What am I doing wrong??