Check this link out from the OFT: http://www.oft.gov.uk/shared_oft/reports/unfair_contract_terms/oft356.pdf It is clear that a requirement for professional cleaning is likely to be considered an unfair term. In general the courts will side with the tenant in these situations if the landlord cannot prove explicitly that that the deductions are necessary. If the landlord does persist with adding new charges make sure that you ask for receipts for work performed and for materials used and keep this correspondence for the court. This will make it difficult for them to make up charges to put you off.