If your values have a price, someone with more money already owns you.

Everything has a number attached until you decide that some things do not. Once a value is available at the right offer, the only remaining question is the size of the offer, and eventually somebody makes it. That makes you predictable to anyone with resources. The protection is not willpower, it is having ruled the trade out beforehand.

Name two things you would not do for any amount, and say them out loud. Do not leave them vague, because vagueness is where the negotiating happens. Everything else is allowed to have a price.