Hi all I have owned boxer dogs my whole life and totally love mastiffs as well I have a question as I'm not sure if I'm being unreasonable in thinking this but we have a neighbour who moved in a year ago in a small flat they have a 3 year old mastif and literally leave it for 10hours aday and they never walk it they just give it 2 mins on the green outside the that's it any thoughts from people that know this breed would be helpful.