Its hard to bid on this project because not all of the information is yet available, but I have assumed that it is just the PCB layouts that you need rather than the hardware/firmware design.
If you do need further design work, then I am able to help with that too, although it would have to be via a separate bid.
CE certification of the type needed for this product would cost much more than the upper limit of the budget, and while some problems can be averted with good PCB layout, a lot has to do with the hardware design itself.