You don’t find out where your line is until someone offers you a reason to cross it.

Lines stay theoretical until somebody makes them expensive. Being certain about what you would never do is easy while nothing is on offer; the information arrives the first time crossing it would get you something you genuinely want, which is also the moment your reasoning starts bending to help. Finding out you wavered is not the failure. Not knowing where the line sits is the real exposure.

Notice when an offer makes something look reasonable that would not have looked reasonable yesterday. That shift in your reasoning is the signal, more than the offer is. Talk it through with one person who has nothing to gain before you answer.