Persimmon, the country's largest housebuilder, built 4,439 homes in the first half, down 5% on the year, which were sold at an average of £162,000. This price represented a 4% decline because of a higher mix of smaller houses. Yet margins edged up to 9% from 8%. The main bugbear for investors is the company's exposure to the North, which could bear the brunt of an economic downturn. Persimmon's valuation is also full, because it has built confidence in recent years and restored its dividend, so there could be better times to buy, says the Times.Marshalls laid the flooring at the O2 Arena in London's Docklands and has also paved Trafalgar Square. It is currently working on projects at the 2012 Olympic Games sites, including installing security bollards strong enough to halt armoured cars. Numis has the stock on a price of 20.3 times estimated 2012 earnings, with a yield of 4.8%. This stock has good potential. Buy, says the Independent.High-performance foam manufacturing may not be the world's most exciting industry, but Zotefoams' products can be found in everything from prosthetic limbs to sporting gear such as cricket pads or ice hockey masks. Like-for-like sales were up by 10% year on year. Still, the company, warned over the effect of high raw material prices on its margins. Hold, says the Independent.Private equity company Oakley Capital has been forced to defend its "cautious" stance regarding the worth of its assets after it reported that its net asset value would rise to 180p a share in the first half. That represents a 7 per cent rise from December's results and a 22 per cent rise on the year, but the company was accused by some of undervaluing its portfolio to ensure that any future fundraising is not diluted by an excessive discount to its NAV. The stock still trades at a hefty discount to its NAV, cautious or otherwise, despite rising 5 per cent on the trading statement, so there appears little reason for buyers to take some time out just yet, says the Times. Airsprung Group has been hamstrung by the weak consumer market and shares in the Trowbridge bedmaker sagged by 9% after it reported that its pre-tax profit had halved in the year to March and warned of tough times ahead. It maintained its dividend to provide some comfort, but investors are likely to rest uneasily given problems elsewhere in the retail market, says the Times.Construction group Morgan Sindall, which issued an optimistic trading statement yesterday, operates across a range of sectors including infrastructure, social housing, fitting out completed developments and project management. It sits on a very undemanding valuation of just 7.7 times this year's forecast earnings, falling to 7.1 times next year. Management say they believe that 2011 will be their worst year, after which things should steadily pick up. If that is the case, these shares could look like a real bargain in 12 months' time. Buy, says the Independent.Please note: Digital Look provides a round-up of news, tips and information that is impacting share prices and the market. Digital Look cannot take any responsibility for information provided by third parties. This is for your general information only as not intended to be relied upon by users in making an investment decision or any other decision. Please obtain a copy of the relevant publication and carry out your own research before considering acting on any of this information.---RG