Thanks for all replies, I've since noticed a couple of gaps in my chicken wire fence around the perimeter, have now plugged them. The fence is about 3 ft high and thought rabbits could jump that, but apparently not, so hopefully plugging the gaps should sort it.......fingers crossed. Can't see any diggings under it either.
I'll still think about the PT, but it sounds like it needs a lot of attention, think I'll wait and see what happens this season, then decide. Thanks again for all inputs. Appreciated.