Recently i recived a job offer for a graphic novel, i have never made one before so i dont really know how much to charge, the novel is supposed to be in color with no so detailed panels but with fully detailed characters, it count with 200 pages.
Seeing another comic with similar style, detail and quality as an example would help to determine a price.
Sandra and Woo: a webcomic about friendship, life and the art of (not) eating squirrels; featuring the girl Sandra and her pet raccoon Woo
200 pages is a big job. How long will one page take you? 1 to 2 days perhaps? Let's say inked and colored 2 days, the project will take you 400 work days which is about a year and a half full time.
How much do you want to get paid per month for the next 18 months? Don't forget you have to cover rent, utilities, insurance, equipment/software upgrades and repairs as well as pension payments and tax.
So assuming you want to have at least $500 in your pocket every week add another 50% for the above expenses( just guessing) to come up with a weekly rate of $750. (That's cheap) So 2.5 pages a week = $300 a page, inked and colored. Less than pro rates, I could take home $500 a week working as a waiter, but if you're keen to break in you might tale a low paying job like that. (Hint negotiate weekly, not monthly)
However, you're going to be working on this for a year and a half, in which time you won't be able to take any other jobs. Marvel could come knocking and you'd have to say no. That fact might mean that you ought to pay yourself more to cover the opportunity cost.
So tell them they can get it cheap at $60,000 , and they'll have it in a year and a half. If they balk, it means they're just playing around and don't really know anything about producing a and marketing a big project like this. If they are a serious publisher, they'll thank you for your generosity in keeping their budget down.
What Atreides says is true. Sadly most publishers these days will not pay you that much up front, so you if you really want the job, you may have to either figure out a process that lets you work faster than that, or settle for a smaller payment up front in return for a beefier royalty (BUT keep in mind that royalties are uncertain and, at best, take a long time to start paying out).
For example my schedule on my last GN was 8 pages / week. I delivered the book a year ago, and it is doing very well, so I will start to see royalties in about another six months. My last two books before that (delivered in 2007 and 2008) have not paid royalties yet, even though they were well-received critically.
It's not an easy way to make a living, though it is at least steady and creative work.