Thanks chaps.
I have been away for the last week, and just before I left I had one of our monthly one-to-one meetings with manager where I told him I did not plan to move with them. There were a lot of other reasons and I would be lying if I said that access to the kind of country I like didn't play any part, but in the end it was not a deciding factor. I would say that had I moved, then all the suggestions that folk have made would have been very useful and would have helped with picking an area to concentrate house hunting.
In answer to Klenchblaize, I don't think that my role is all that specialised, I am a mechanical engineer with experience of designing the mechanical parts of motors and generators. Electric motors and generators appear in a lot of products, but even if I look at another area I have transferable skills. Only one of the designers we have taken on have had previous experience in motors, the rest have just had some experience with rotating machinery, and they have all worked out fine.
Thanks again folks. You have been a great help!