To be able to quote a fee accurately you need to obtain the information detailed below. The client should have most of it available, so you can ask them directly. Accurate licensing is mutually beneficial for the client and the illustrator as it defines a fee for actual usage as required by the client, rather than possible usage.
If you’re asked for a ‘ball park’ quote by a potential client tell them that you can only quote on what they know they want to use the artwork for. How can you work out a quote for potential uses you don’t know details for?
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