Creating a music arrangement for a client, contracts, iTunes etc.


So, a singer-songwriter asked me to create backing music for one of his songs, which I did. After a while, he decided to start selling the track on iTunes, but had some basic knowledge about licensing, royalties and such, and a couple of days ago asked me for advice on how to approach the potential money income and avoid author’s rights issues.

My question is, how differently do you price your work when the final product is going to be used commercially, how often do you release all usage rights to clients and how are contracts made in regards to splitting credits and earnings to people involved in a track when, for example, the track is being sold on iTunes or a similar platform?