Why didn't my solicitor say how expensive it would be to extend a lease?

Q In 2006 I bought a flat with an 81-year lease. The solicitor asked about extending the lease and the landlord responded that it could be done under the normal statutory rules. My solicitor made me aware that this was fine and after two years I would be able to use Section 41. What I was not told about was the crucial 80-year period, at which point it gets a lot more expensive to extend the lease. In August last year I started proceedings and it looks as if I will be paying around £13,000 to extend by 90 years. However, I am annoyed my solicitor did not explain the 80-year rule and I feel that had I known about it I would have made sure my initial offer took this into account. Can I seek redress? I am using the same solicitors for the lease extension. SB A If you are serious about seeking redress, you should take your lease extension business to a different firm of solicitors. Then you'll need to make a formal complaint to the solicitors which failed to point out the 80-year rule to you at the time you bought the flat and set out what you are seeking in compensation. If you cannot reach agreement with your solicitor, you should then be able to take your complaint to the Law Society . You are right in saying that where a lease has less than 80 years to run it gets more expensive to extend, because any valuation of the lease extension takes into account what is known as the " marriage value ". This is arrived at by taking the value of the property before extension from its value after extension, and adding the landlord's interest – typically the loss of income from ground rent for the remainder of the original term (as the whole of the new lease will be at a peppercorn rent ). But it is also worth bearing in mind that because this "marriage value" is split 50/50 between landlord and leaseholder, the cost to you of extending a lease should always be less than the increase in value created. So although you are spending more than you might have to extend the lease, you haven't lost out because the increase in the value of your flat once the lease has been extended will be more than what you have spent.