Saw a few Sergei types in a hotel just outside Cambridge a few times, tended to sit in a quiet area on the second floor checking phones and laptop, never spoke to them and might be me being suspicious / cautious when walking to the room.
Similar to Northface, saw the Chinese equivalent the first time I punted a Chinese girl (well, granny more like). He seemed friendly, enough which was good as he was brandishing a meat cleaver whilst cooking lunch as I left, a bit disconcerting.
As for 'Sergei' I had the impression that 'he' was more the man who did the driving between the various flea pit hotels and working flats. The maid on the other hand was covering prossies in different hotels, probably no where near any of them.