Home sellers' packs aimed at speeding up the home-buying process in England and Wales will become law on Thursday.
The packs are designed to speed up the home-buying process
They will force sellers to have surveys and local authority searches done before putting properties up for sale.
But critics say Home Information Packs, which will cost about £600, could go out of date before properties are sold and are a waste of money.
The Housing Bill comes into force on Thursday, but the seller's pack will not be compulsory until 2007.
Pilot schemes are due to start in 2006.
The government says the Housing Bill will "help the most vulnerable and help create a fairer and better housing market".
Hundreds of millions of pounds are wasted each year when sales fall through before contracts are signed.
'Through the wringer'
Housing Minister Keith Hill told MPs on 8 November: "Hundreds of thousands of people every year are put through the wringer because of the inadequacies of the current system."
The Commons overturned peers attempts to make the packs voluntary - Mr Hill argued sales chains could be disrupted if one seller did not use them.
But some professional bodies representing lawyers and estate agents are sceptical about the packs' merits and "shelf life".
They say parts of the pack, such as local authority title searches and home condition reports, could soon go out of date.
Peter Bolton-King, chief executive of the National Association of Estate Agents, warned that the cost could put people off selling their homes.
But, Which?, formerly the Consumers' Association, supports the packs, arguing they will increase transparency and cut the time it takes for a house sale to go through.