Sally,

I hear ya on the "deadbeat" gallery that doesn't pay or care about doing a good job for you. Most of us have horror stories like that.

The best thing is to get references from other artists and if the gallery wants to sell your work, make sure you're comfortable with when and how they pay.

I'm so glad to hear that you've found a gallery that is honest and goes to bat for you. That's what they should be doing.