Got roped into being the sound operator for an amdram show about 3 days before the dress run, I'm only doing it to save face for the society putting the show on but sorta regretting having to do a mediocre job for the next week and getting paid a sweet, phat sum of £0
At what point does one consider themself good enough at a certain thing to start charging a decent amount of money without being overbearing? I've exactly this same issue when doing posters / graphic for folk, as well as DJing. I know enough to gauge that I'm absolutely not the best at a certain field, so continuously undersell myself because I'm completely unaware of the limit of my abilities and what I'm actually worth / valued at
From my experience when people get to know you a bit, meaning you did a few jobs here and there for free and they were satisfied with your work, they tend to ask (or offer) how much its going to be the next time. I don't see any problem working for free for some time to gain experience, however someone will definitely try to take advantage of you at some point you just have to know when to put your foot down and tell them. It usually happens to be these short notice jobs, though you can also charge them extra Remember time is money and if you are good at what you do don't do it for free.
That said, gauging how much to ask can be hard. Try to find out how much other people are asking/making for a given job and adjust accordingly.
With my band we can get anywhere from $200 - $500 per show but honestly we'll take just about anything so long as we can play somewhere.
That being said though, all the members have stable well paying jobs so music is just fun and the money we do get just gets re-invested into the band for equipment / gas money / studio time.