@gpedro At the end of the day it has to be a zero sum game and in any reasonable run of time the main determinant of what you earn is how many TB do you have.
So if the Renter makes more than the "Going Rate" then the Owner makes less and if the Owner makes more than the "Going Rate" the Renter makes less.
In practice as the Owner is calling the shots he would be stupid to make less than the going rate so it's always has to be the Renter that looses out....
Perhaps to simplistic a view, but it's my experience of any sort of Miner Rental.
Rich