Graphic Designers are often underrated for the value we bring to any venture. The prospective clients some times fail to understand how much work is involved in conceptualisation, design and digitisation. This results in a devaluing of how much a particular graphic design project may be worth; ergo being asked to “work for FREE”.
I think with any opportunity, you have to evaluate what taking on a specific project is going to mean for you in the short, medium and long-term.
I’ve done work with several non-profits with noteworthy projects that have included outreach to children through sports or creating local economic development within varying communities and each one has been a different experience. Some of these projects have led to other spinoff opportunities such as networking, free publicity and meeting prospective clients and admirers of a specific design you may have done.
Give advice for free, but limit the advice (not unless they’re going to hire you). At the end of the day, you can work for free, but never sell yourself short. Always ask for something in return. Bartering never gets outdated.