Interesting concept Charlya - my immediate response is that I don't know. But I would liken this to some sort of signage or billboard usage. Your image will have to be converted into some sort of decal or the equivalent.
1. Will she be picking up the cost of the "wrap" in addition to whatever you charge for use?
2. Do you like this coordinator and not mind having her use the image?
3. Will you have some sort of photography tag line on the wrap off somewhere to give you credit (that could figure into negotiating a price)?
4. Do you know how long the "wrapped" car will be in service?
5. How established are you, and how much are you in demand? This will figure into your value.
I don't find this type of question annoying at all as it's a little different than the others. Basically you have entered the realm of advertising photography which can involve a lot of custom pricing. I'll be interested in seeing some other comments.