@Crewey
I own low value commercial buildings and know about this. Bottom line is that you never, ever want to go anywhere near a court as the costs go turbo and potentially out of all proportion to the sums involved.
With commercial property the default position in law is that the tenant has a continuing right to occupy provided they pay the going rate. If the parties cannot agree the going rate I believe that the courts ultimately decide it.
From a landlord's perspective the problem with this is that they cannot evict tenants if they want to do something else with the building. ie the tenant is abusive, or is polluting the local environment with fires/ leaving transit van engines outside, upsets neighbours etc
Evictions and enforcements are horrible, expensive processes so from a landlord's perspective the easiest way to remove a problem tenant is by the lease expiring. But with security of tenure there is no expiry date.
The landlord can override security of tenure if circumstances meet a very high threshold ie the building is to be fundamentally redeveloped and this can't be done with the tenant in situ. Or if the landlord wants to re-occupy the building themselves.
To exclude security of tenure the tenant must be informed about this via a formal notice and declare that they understand the consequences. You either have a 2 week cooling off period between issuing the notice and signing a declaration. Or the timetable can be compressed if the tenant signs a stat declaration in the presence of a solicitor.
Business rates fall on the occupier. Maintenance can fall on the owner or the occupier, depending on what is agreed.