Tenants are expected to return the property in as good and clean a condition as it was when they received it, fair wear and tear excepted. If evidence (receipts or settled invoices) was provided by the landlord or agent showing the property was professionally cleaned immediately prior to the start of the tenancy, it is reasonable you should provide similar evidence at the end of the tenancy. Standards of cleaning can vary, even amongst professional cleaners, so for the avoidance of doubt, where possible use the same company to clean the property at the end of the tenancy that cleaned the property prior to the start.