Analyzing a Flip - ARV rule of thumb

[Bryan Cifuentes]

Ok, so I'm a bit confused on the rule of thumb is for analyzing a flip. Is it 70%-75% of ARV minus repairs? I've come across a property that is preforeclosure at 255k. (Listed)

ARV is ~ 315k

Repairs ~ 40k

That leaves me at 81% of ARV.

So assuming I negotiate down to 75% of ARV. I'm at 236k.

Do I now deduct the 40k from this and offer 196k??

Or is the rule of thumb 70-75% of ARV and no repair deductions? So now my purchase is 220k-235k?

Please clarify because I've done the Flipping Calculator on here and it appears to follow the ladder?

I've kept an eye on flips in my area and I see that investors are offering 70-80% of ARV and they purchase at this price.

Any help is appreciated!