It is currently very difficult to obtain third-party liability insurance without a FLM Pilot rating. Generally the rating will remain valid for life so long as the pilot is a member of one or other of the participating associations. There are no particular restrictions for foreign pilots except they must comply with airspace regulations Etc. Wales and Scotland provide more rugged scenery but the vast expanses of East Anglia are just as interesting, and a navigational challenge. Central England probably has more clubs than anywhere else if you want to make just short cross country flights.
Many schools offer generous training packages attached to the purchase of a new machine.
As the sport is so new, second-hand machines are rare.