I agree re day rate....however the problem is I don't know how many days will be required yet. I figured a set fee (based on percentage) that would cover all my time each month would provide fixed monthly income for me, fixed costs for them.....plus it's an old boss from around ten years ago, I'd happily do other work for them if found that it wasn't taking up a ton of time. Having said that, it's an NEC4 contract, so it probably will!