To make a (really) long story short .. I've edited this piece of text over and over again, written paragraphs and then deleted them.
For me, future prospects are more important than current salary. 10 years ago I earned 20k a year but it took all my time. Now my jobs earn 20k a year with 25% of my working hours invested. The rest of the time goes to improving my career opportunities. I think my current situation is immensely better, even though my earnings are the same.
So, what's a comfortable salary for me? When is a job good enough that I would skip career advancement opportunities in favor of current job? Probably near 70k a year. What's a salary I can live with (at least for a time)? Probably near 20k a year. (euros).
*edit*: I'm always thinking about my current hourly wage, how much I can have of it and how it compares to career advancement opportunities. I'm almost tempted to start earning 70k a year now, just by skipping school and taking more work. I'm just afraid it would be temporary. So I think I should continue to increase the value of my work before I stop educating myself. This has been a tired post by a tired person so it's not entirely accurate, but it's accurate enough.
*edit2* I won't get enough hours/month to make 70k now, so it's a non-issue.