if you did all the 3D work as well as the flash, other graphics, and html, then I'd probably charge about £1500 for that - of course it depends on the client, what you think you are worth an hour etc.
The way we generally work it out is:
number of hours estimated: say 35 hours X £25 = 875
PLUS
Project management (this is for all the planning, mock ups/concepts, phone calls, meetings, changes of plan etc.) normally somewhere round 25% of your development time in addition
= £218.75
Total = £1093.75
But of course that's not mates rates. Thought to be honest, I'd steer clear of doing websites that involve 30 odd hours of work on the cheap, even if it's for mates, you'll soon get well narked off with it. Unless you're just doing it for the experience, in which case do it in exchange for a few crates of beer
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