Thanks folks, some damn good leads there. At the place I intend to do the main effort, there is a fair bit of space, and also a fully equipped engineering workshop, with lathes, and CNC milling machines, laser cutter for wood, and a 3D printer!
I'm just hoping that any crashes that will inevitably happen, are not such a high velocity that the GoPro can't take the G forces! We have to fly something when we go there, last year it was Pascal with a ducted fan f86 sabre, which was a disaster, and me with a really basic foam R/C plane, which was merely mostly unsuccessful, rather than disastrous.
At least this time we will be hoping for a bit of wind, instead of hoping for dead calm. Hopefully i can get it sorted by July. I suspect I may find out the true range of the wifi on the gopro! I know it struggles with being 3 floors away in an ancient stone building, but maybe it'll work at max kite height. If not, it'll be back to the old fashioned way of firing it up manually before we take off.