Hi,
mine only walks dogs from the same home out together unless specifically requested and even then she doesnt take more than she can cope with (depending on which dogs this could be between 1 and 4). i am pretty sure that HoP are the same 🙂
cuts down earning potential but mine get a lead walk using my cues walking to heel under control to the park and then free running and walk back just the 2 of them. i dont think you can compare that to the london vans as its a different situation 🙂
Claire x