Thanks :)
I don't do a great deal of highway driving. It was more of a challenge to see if I could pull it off.
The parts costs are very variable. I did it pretty slowly partly because I was prepared to wait for the right price on parts to come up.
I sourced parts from all over the world.
For example the radar module itself is about 2000Euro new but I managed to find one in the Netherlands for 200Euro.