1 and 2 This Mercedes Sprinter is pretty standard except for the fact that it is a 4x4.
3 and 4 The German MAN with Bimobil body is a popular rig amongst the hardy adventure types, but this is the first I've seen with British plates.
I met the owners of the MAN (Michele and Stephen) and they are indeed from the UK. They have a very detailed blog / website to track their travels:
if that does not connect try this one: