When pricing such a large project that has a pretty quick turnaround, make sure your friend states that he will do, let's say, one round of revisions (author alterations), but anything past that will be charged at his hourly rate of $55. This way, if he quotes a flat fee per piece, he is not altering them a thousand time before the author decides it's OK.
Also, many of these projects require that the artist sell all rights--a bad deal, but unfortunately the way many publishers operate. At the very least, even if the publishers want all the rights, make sure the art can be used for self promotion (I guess this is pretty much what Roberta has mentioned).
Another thing--depending on how the project is structured, he can offer 2 or 3 price ranges for art--for simple/moderate/complex and come up with a tally of what he considers those ranges. If they just want a flat rate, do that anyway in calculating the total cost and then divide by 290. I hope that isn't too simplistic an explanation.
Just a few thoughts on the matter!
Take care and good luck to your friend,
Wendy Beth Jackelow
Medical & Scientific Illustration
266 Pelton Avenue
Staten Island, NY 10310
Tel/fax (718) 273-00002
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