(ShareCast News) - Shares in Concha should be sold, said the Sunday Times' Inside the City column. The cash shell's shares have plunged after chairman Chris Akers failed to seal the deal on a "specific global opportunity", with nine months of talks coming to an end last Thursday. The share price now values the company at less than £10m, with £5.7m cash in the bank.On Tuesday the AIM-listed shell company, which has made two investments since listing though both have gone 'pear shaped', is due to release final results for the year. The board should share their plans on how the cash will be used after the ending of these long-running talks and may also explain why no annual report has been published since 2013.Shares in Sigma Capital Group are worth buying, said Midas in the Mail on Sunday. The share of owner-occupied property has fallen from 69% to around 63% since 2001. Added to the rental accommodation mix of social housing and individual landlords is a new trend for purpose-built rental homes owned by companies, including Sigma since it changed direction to focus on urban regeneration and rental accommodation in 2011.Sigma has partnerships with housebuilders Countryside Properties and Keepmoat Homes and with Shepherd Direct's Central Lettings arm, as well as securing £200m funding from the Kuwaiti-backed London-based Gatehouse Bank to build a minimum of 2,000 homes and up to 10,000 more before the end of 2020. Sigma has built close to 350 houses so far, with a focus on family homes to attract long-term tenants, and almost 1200 more are planned for the end of 2016, with a further round of 550 internally funded homes the year after. Profits of £1.5m are forecast this year, more than quadrupling the year after.Questor in the Telegraph examines exchange traded funds (ETFs) as an investment option for retail investors. ETFs are branded as a simple low-cost investment option for those that want exposure to specific asset classes, but while their shares can be traded on exchanges, the fund's underlying assets can range from corporate bonds to commodities like gold. While ETFs normally issue shares to satisfy demand, when hedge fund want to take a short position in the ETF then it needs to borrow the shares from someone, market makers sometimes match the two trades and the ETF does not need to buy the underlying assets, leaving the retail investor on the other side of a hedge fund trade.If the hedge fund collapses it can cause trouble for the ETF and those ETFs that use derivatives can also run into trouble if the financial institution issuing the derivative runs into trouble. While ETFs have closely tracked the prices of the underlying assets and offering liquidity to retail investors this year, volatile markets will test these financial products.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.