Candidates often struggle to "do the math" on an offer because they focus on top-line goals instead of monthly goals.Here's a situation. You have a $75k offer, but are used to making $100k. If it takes you another three months to find a $100k job, your earnings at the end of the year will be $75k.In your second year, you'll make $25k less.The math isn't based on these numbers. It's based on how much you have in savings, your monthly spending, opportunity cost, and your willingness to leave or stay at a company.If you stay 10 years and aren't promoted (you never count on promotion or raises), you lose $250,000. If you leave after one year for a $100k job you break even.It is possible to take a job at a lower level and salary and do fine. I did that, and it took me four years to get back to a salary level I thought was commiserate with experience. In that three years, I drastically altered my spending, enjoyed stability during a rough patch, and thrived.But I went into it with eyes open, glad I was even employed.The real challenge - is how you coach a friend on an offer without saying something as dismissive as "do the math."