That is an important point, which I will come to.

Purchasers living in flats are required under the terms of their lease to contribute towards costs through service charges, although providers may set up and manage a sinking fund to cover the cost of major works when the lease allows. When leaseholders contribute to a sinking fund, it may help to lessen the impact by spreading the cost over a longer period and minimising demands for service charges when the works become necessary. The Tenant Services Authority requires registered social landlords offering shared ownership schemes to explain the features of the scheme, so that applicants may make informed choices on whether the scheme is right for them. Applicants will have the level of service charge, rent, mortgage and other outgoings taken into consideration to determine whether the applicant is able to afford the purchase, as well as their ability to sustain home ownership in the long term. The TSA also expects RSLs to levy service charges that reflect the actual cost of services provided, and any increases should reflect the rise in actual costs. The Homes and Communities Agency expects grant-funded shared ownership schemes to be affordable to the intended client group.

Shared owners contributing towards the costs of repairs and maintenance through their services charges may challenge them through the leasehold valuation tribunal when they believe the charges to be unreasonable, and they may receive free advice about that and other rights available to them from the Leasehold Advisory Service. I am aware that service charges, including charges relating to management, are a matter of concern to those who have purchased their property. Free legal advice is available on the various remedies available to shared ownership and other leaseholders when faced with a service charge demand that they believe to be unreasonable.

In December, the Government issued a consultation paper setting out how we will reform housing benefit to deliver a simpler and fairer system of housing support that pays a fair rate of benefit to customers while protecting taxpayers. It also sets out our long-term aspiration to move towards a housing tax credit that is properly integrated into the wider tax and benefit regimes. As my hon. Friend the Member for Islington, North knows, housing tax credit is not something that we can implement overnight. Such changes will take time to achieve if they are to be affordable and achievable. We will ensure that the changes go hand in hand with wider housing policies to build more social and affordable housing in mixed communities.

The consultation sets out our next steps for reforming housing benefit and includes those measures that we want to implement quickly, as well as those that we will deliver as part of our longer-term reform of the benefits system. As part of the consultation, we sought views on how to set fairer and clear benefit rates. The local housing allowance is set at the median level of rents in an area and is intended to ensure that approximately half the properties available to rent in any area are affordable to people receiving housing benefit. That balances the needs of customers, enabling them to afford decent, quality accommodation, with the needs of taxpayers not to subsidise unreasonably high rents.

We must consider again how we set local housing allowance rates, and examine the effect of areas with pockets of high rents in driving up the median. We also want to consider how to define geographical areas for local housing allowance rates. We recognise that rents vary significantly throughout the country, but in London they are typically much higher than in other areas. High rents mean that, after housing costs have been taken into account, people are more likely to live in a low-income household in central London than in any other area of the country. There also tends to be wider variation-