In my view the numbers are always too variable to discuss reliably. The amount of detail you would need to provide on the client and the project at hand for people to really help you with the numbers is very likely to piss off your client!

In terms of exclusivity versus not, the difference is proportional to how much you can sell the design via retail yourself. Over time this is generally not negligible; also, the perceived difference can be used to manage the price negotiation, for example by giving the client a chance to fall back on a less expensive option than full exclusivity, without running away outright. But if you think the sort of design they'll end up happy with won't sell well in the open market, try to sell them perpetual exclusivity. In any case though, unless there's a specific technical issue that no existing font in the market addresses, some exclusivity is only logical, otherwise their competitor(s) can buy the font retail and sabotage them.

In fact this "some exclusivity" tends to make great sense because clients like this only need the "novelty effect" for a while, maybe 2 or 3 years. Such a scheme is common, and can strike the best balance for both parties.

hhp

A grant of say, exclusive use for not more than 10 years (with an option to buy an extension thereafter), and/or reversion to the author after a period of 2 years of disuse in defined areas, would not be unreasonable, you think?

Numbers are just for examples' sake. Your specifics may vary.

I have in the past purchase single project usage rights to corporate fonts and paid $300 for 3 fonts (REG, ITALIC, BOLD). If this gives you an idea of what can be earned on the side if the font is only semi-exclusive I hope I have been of help.

I don't really understand what alchion said. Can anyone translate this into plain readable English? Maybe himself. Single project usage rights, corporate fonts and semi-exclusive... Am I really that stupid?

Enlighten me please.