In regard to an hourly rate for the ento project:
When working on a big book project or any really large scale project, I
find that hourly is not really an appropriate way to bill--If one were to
add up real time and bill at $50 per, you would present an estimate to you
client that would be astronomical.
Better to estimate on a per piece basis--itemized by projected complexity of
art. e.g: simple figures $x-xx, moderately complex figures $xx-xxx, complex
figures $xxx-xxxxxxx, etc.
Clients understand this better, and this system empowers them to make
certain choices--they have the option to cull less important figures, etc.
Clients can agree that a certain figure has a certain value by virtue of its
complexity. For instance, a client could see that a fully rendered pic of
a beetle is worth $250 (or whatever) and that a line drawing of a grub is
worth $50. They can't always understand $50/hour (although I fully agree
that it is a fair price!), and they do tend to flinch when you mention this
kind of number. An hourly rate appears to have no ceiling to many clients,
and they get scared.
It also allows you to stick to your estimate better, and to work more
efficiently--you will get faster and better automatically, because you will
be challenging yourself to 'meet the mark' you have projected for yourself.
Of course, and hourly structure can be built into the per piece price, as
well as computer overhead.
We can never truly bill for all of the time we put into a
project--especially when there are unknowns in the mix, such as computer
malfunctions ...but if we estimate carefully, fairly and honestly, and
explain it carefully to the client (the education of the client is
important), then we have been fair to both sides. We can thus eliminate any
adversarial air between ourselves and our clients.