All artists should not charge money for their wares. Isn't it payment enough to see your creativity, consciousness, product, distributed amongst the people? Which in turn makes the people happy and perhaps inspires their creativity and enlightenment to create something in both of your names. If someone accepts such a gift (fruit of creativity) that you have made then you have the right to find out what that person is creative in making or doing and if you need their services for you or a friend then that person should not deny you but add you to their schedule. Such even exchange is not a requirement unless you would like their services. Not because you want payment. Services are not to be compared. Each service is equal due to the fact that they all benefit the community regardless of time, materials, or creativity put in. Also if you receive from another and they wish you to dine with them you should not deny them their hospitality. Remember that you already have your true payment by inspiring and / or helping others with your wares. It is also a great honor for someone to ask if you would use your talent to create something in their image. This is an honor because this person has faith in your skills and will spread your name and craftsmanship to others. Not only that but you will be inspired by their creativity which may evolve your creativity and / or craftsmanship and thus you.