Thanks for all the feedback, everyone.
Quote Originally Posted by daveob View Post
Perhaps you could do the PR exercise of sitting down with the client and explaining so they understand how they can save themselves from being over-charged by "just in case" over-quotes.

Best case result : you get mega brownie points for being honest and working with the client. A good & honest reputation is worth a heap load when it comes to deciding on the company to use.

Worst case : you walk away and don't look back.
Tried it - not sure we even got brownie points for being honest...

We've solved it by breaking down the broader work objectives into bits, and submitting separate, accurately assessed and clearly specific quotes. If there's something that's not covered among that lot, it's not covered.

Might mean we only get parts of the work, or none at all - but I'll sleep easy however it goes now.