Once a lease is signed by landlord and shop/land renter they are both legally bound to fulfil all conditions, such as paying rent, for the full term of the lease. Verbal agreements to change the lease are never binding.
If a landlord or company leasing the premises and renter want to change the originally agreed upon lease, this must be done in writing by solicitors. Both renter and landlord must agree to any changes.
If both landlord and renter understand and agree to the lease conditions, there should be no disputes. This is why it is essential that all terms and conditions in the lease are clearly worded and cannot be misunderstood.
Common areas for confusion include rent increases and lease renewals however there are many other areas disputes can arise.