Plans to levy capital gains tax on property owners who hold their homes through a company structure risk discouraging investment in the private rented sector, tax specialists and investors warn. Scott Nicol, vice-president of Gatehouse Bank, which channels Middle Eastern investors' money into UK property, said he was also worried about the proposals. Gatehouse backed Sigma Capital last year to develop 6,600 privately rented houses in a deal worth £700m. If all the homes are built, Sigma will become Britain's biggest private landlord.