Here’s a longer response to a colleague who was frustrated about the ridiculous price offer made by a potential client:

I understand the frustration. Price negotiations should be brief and focused, but not bitter. For this, you MUST know what price you’re aiming for.
IMO the client was willing to negotiate and they wanted to work with you, they just needed a transparent pricing basis to tell their boss.
If you feel there’s a ” volume risk”, just give a higher estimate to cover this risk. In Germany pricing is based on lines of 55 chars, because official documents often come on paper. So you visually count down the lines on each page and multiply that by your target line price (1-1,20 EUR for common combos). But I use that only for internal calculation to know my minimum price. Anything from the weather to annoying e-mails can alter this rate.
In your case they were willing to pay 940 x 0.14 = 131,60. You should know your target price, so let’s say you know it will cost you around 7 hours @ $30 = $210, add around 40% annoying client surcharge + rush fee and you have roughly $250. Now all you need to do is pitch it – tell them why they should pay you 250 instead of getting it for 70 on ProZ.
Remember, the communication was frustrating for them as well – and still they persisted, because probably they found no one else. Don’t give up this advantage!
“Dear Joe, thanks for making the effort to give me a precise word count. As I also want you to know what to expect, I took out my pocket calc. I can offer you to finish this project at USD 250, delivery until xxx, all eventualities/rework covered. I hope your weather is as nice as mine. Unfortunately I’ll be spending all day with my kid at the dentist’s… Arg… Bills, bills, bills….”
Cheesy humor and weather talk, etc. really help!