I would suggest a few things
1. When they call you, or ask you to come and play.
A) Ask all the questions you think you should ask. Like,
1. How many rehersals are there?
2. Do I have to bring my gear?
3. How long is the gig / service?
4. How much is it paying?
5. How many songs?
All these questions determine what you should charge.
And the second you hear these words spoken, "Awwwww man don't worry about it I'll take care of you, you'll get paid!" RUUUUUUUUUUUUUUUUUN AS FAR AS YOU CAN SEE!!!!!!

or just simply say :oNO!!!! See people will only do what you let them do! I say NO! To stuff all the time and most of the reasons I say NO! Is not because the money is wrong, but because the person is wrong! Anytime someone ur doing buisness with is not upfront with you, for example,
1. If they don't look you in the eyes and talk to you, DON'T BELIEVE A WORD THEY SAY!
2. Anyone that never gets to the point of the buisness or expectations of the job, DON'T BELIEVE A WORD THEY SAY!
3. Ecspecially ya "Boys" make dem dudes keep it real with you about everything concerning the buisness!
4. And people that can't ever make up their minds about what they want "Watch them 2!"
But also remember some things you should do strictly based on relationships. I've said many of times on this forum, that relationships mean everything is this buisness, so be wise about how you do ur buisness and careful about the relationships you subject urself too. My Mom once told me, "Never get involved with someone that has less to loose than you do!"

and never forget this, Its ok to say, "No I'm good but Thanx for asking!" Fellas All opportunities aren't good opportunities and all good opportunities aren't GOD! opportunities! I Love you guys, and I'm praying for you! And you should be tired!