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In an initial interview, I told the company, which is a non-profit, that their salary range was OK. Non-profits typically offer lower salaries than for-profit, so this is not unusual. But trying to negotiate for a higher salary simply wouldn't be possible. I thought I could live with a lower salary, but I realized I could not. It would require a long-term change in lifestyle in order to make ends meet. On the one hand, I really need a job. But, on the other, accepting this job, as-is, will have long-term consequences.
Now I'm a few interviews in, and I am afraid they will eventually want to hire me at this low salary. I am actually losing sleep over this.