I've been contacted on LinkedIn by a lawyer and his clients. They asked me if I would be interested in reviewing a piece of source code and answer specific questions they have about it such as whether it performs this or that function, how long it would typically take to write such code, etc.
I'm qualified to review the code and provide detailed, argumented answers to their questions, and I would be delighted to help them. However it would be my first case as an expert witness and I'm unsure about the quote I should give them.
To be more precise, I need to provide a quote for an "initial review" which they estimate would take around 8-10 hours (which I think is entirely reasonable even if I may adjust this slightly). I would also need to travel (international, 4-hour flight) to attend a cross examination that they estimate would take 2 to 3 hours (but at least 36 hours in total if travel and accomodation is accounted for).
Even though I did consulting for a few years a long time ago, I'm no longer self-employed. I'm a principal engineer in a software company in an entirely unrelated line of business. However I have a strong presence in the open source community and it's as an open source project leader and software author that I would testify (in my free time).
As an established software author in France with around 20 years of experience in the field related to the code I'm being asked to review, what would be a reasonable hourly rate? Beside the 8-10 hours for the initial review and the 2-3 hours for the cross examination, what else should I bill? Should I simply increase the hourly rate to account for the 36 hours of travel time, or would they typically pay travel (and related) expenses?
Thanks for all the help in this new exciting adventure. Quick answers are appreciated since the timing is rather tight on this one.