Calculating how high you are willing to pay

For you guys buying sites, how are you calculating the amount you're willing to pay?

I guess you can start by knowing or predicting if that site you are about to buy is using blackhat or not. If the site is using blackhat, I would only go far as multiplying the claimed monthly income to six. As we know blackhat method is unstable and not guaranteed in the long run.

Many websites are 100% WH and when the revenue is rising month on month the greater the value of the site...

Some selling prices are off the richter scale and many do not even attract buyers...

Folks say there is a monthly income multiplier, but all sites are different...

Hence look at a site individually, then do background profiling and due diligence before putting in an offer to buy!