I've been asked to do free photography, do taxes for friends (10-15 people a year), loan instruments (all of the time), contribute finished films...everything I do, including playing.

For friends, I may play for a retirement dinner and just not send a bill. Once a week, I play for a private party and have a check cut to my Nursing Home reform charity. That way, the charge is tax deductible.

My experience is, if someone asks you to do anything free, that's what it is worth to them.

Russ