The US private investment firm looking to buy Tottenham Hotspur is today revealing another push into the London market with a £400m development in Islington.Cain Hoy, which last week confirmed it is considering a cash offer for Tottenham, is partnering with developer Sager group on a joint venture to develop the 4.5 acre Islington Square site.Cain Hoy, founded by leading figures from global investment firm Guggenheim Partners and named from the racehorse stable owned by the Guggenheim family, will fund the development to create a mixed residential, shop­ping and leisure district.Cain Hoy’s European investments are led by Jonathan Goldstein, who previously worked at Heron Tower developer Heron International.Work on the Islington Square development has already begun, and is expected to finish by 2017.