Some of the occupants covenants in a lease can impose restrictions on its occupation of the premises which, when checking the rental value of the property at rent review, can warrant an alteration in the rent. If the premises were offered in the open market on the same tenancy terms (and a discount could be expected in any open market bids), to reflect the onerous lease provisions when  compared to the ‘market norm’ for the class of property concerned, a similar discount can be applied to the rent review.