The Letting Centre

My fiance and I live in a 1 bedroom flat in Gillingham. We've been there for 4 months and are model tenants - always pay rent on time, very house proud, etc.

We have a assured shorthold tenancy agreement for a fixed term, ending this October. We would like to stay at the flat beyond this period. The letting agent has asked us to pay a renewal fee of about £120 prior to the new AST contract being drawn up. I have been told that the contract will be exactly the same as the previous one, just covering a different period. I don't understand how they can justify charging us this amount of money. Is this normal or are we being ripped off?