The best reason for adding an extension or renovating your home is that it will improve your quality of life. But nobody wants to see their money go down the drain.
And with rising house prices pushing up the costs of stamp duty and estate agents' fees, more people than ever before are looking to upgrade rather than move.
"With the latest housing market reports showing the market too be slowing down, home owners could add significant value by looking at ways to improve their current homes, rather than move," says Zopa Giles Andrews, chief executive officer of peer-to-peer lending organisation Zopa.
"With record low rates on borrowing, home improvements can be a cost effective way to add value to your property for the long term."
Now, Zopa says it's looked at different home improvements, and worked out which offer the best return on investment.
The average project adds 10% to the value of a home, says Zopa, or an average of £30,000 - representing an 80% return on investment. This, though, masks some big differences.
The most popular project, says Zopa, is to install a new kitchen, accounting for 30% of the company's home improvement loans. But it costs an average of £9,600 and gives a profit of £4,750, making for a return on investment of just 49%.
It's a marginally better investment than replacing the bathroom, which costs an average of £4,900 and delivers a profit of £2,350.
At the top of the scale, adding a conservatory is the best investment, more than doubling a home-owner's outlay. It costs an average of £5,300, but delivers a 108% return on investment.
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But what about more eccentric changes to your home?
A new survey by Move With Us of its network of independent estate agents looked at some of the more unusual additions to houses up for sale. And, it found, a cinema room or outside office can add 5% to the value of a home, while a man cave, tree house or sauna add 1%.
""More unusual home improvements are increasing in popularity. Home owners are ingeniously creating new spaces within the boundaries of their existing homes where they can live out their dreams. These include garden offices so they can work from home, workshops where they can carry out their passions, their own personal pubs and all sorts of other extraordinary structures," says director Simon King.
"It's great to see home owners using skill, imagination and working within planning permission guidelines to create exciting new spaces which have the added bonus of boosting the value of their property."
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