Just to add a couple of points here to the discussion that may go on the minus side against the Airbnb idea...
(1) The rental income I get from the property provides about 50% of the income I live off. Airbnb may prove more profitable, but the lack of certainty around what actually might be coming in each month is a potential drawback.
(2) The location is Camden Town, which does attract a younger party crowd looking to experience the vibrant nightlife. So there is a risk of tenants perhaps throwing parties in the property itself. This could be expensive and time consuming to clear up; even though my friend has said she will take care of all of this side, it may prove more than she has anticipated. And it could also prove disruptive to neighbours.
A couple of things for me to think about!