'I signed £1.3bn rent contract by mistake'
Luke Mosson bought a flat for £150,000, but later realised that a clause in his contract meant the ground rent over the whole lease would cost more than £1.3bn.
He is now negotiating with his landlord to be released from that clause.
James Longman reports for the Victoria Derbyshire programme.
Watch the full report on leasehold contracts here.
The Victoria Derbyshire programme is broadcast on weekdays between 09:00 and 11:00 on BBC Two and the BBC News channel.