Paint: Kiln fired vitreous paints are used, which last for 100+ years depending on the weather conditions. They are fired to 1,100+degrees Fahrenheit.
Add $10-$75 per painted piece included in your panel. The number of painted pieces to achieve the desired effect will vary and is part of the conversation.

Silver Stain: Turns clear glass yellow in the kiln $15-$100 per piece. Useful as a design element when one wants more color on a piece without making more lead lines.

Etching: Add $10-$50 per etched piece. A resist or stencil is used

As an aside: Technically, "stained glass" refers to painted or silver stained glass. In Europe most people call unpainted but colored glass "leaded lights" .