Max offer for flip formula?

[David Sanford]

ARV of $200,000. repairs needed $25,000. I would get a hard money loan at 12% interest. after realtor fees and holding/closing costs considered, what should my max offer be? my math is this: 6% realtor 3% closing costs 6% hard money interest assuming 6 month flip 15% total $200,000 x .15 = $30,000 $200,000 - $30,000 = $170,000 $170,000 - $25,000 (repairs) = $145,000 $145,000 - profit goal of $20,000 = $125,000 $125,000 Max offer. am I off?