A Dublin property company has been assembling a portfolio of apartments throughout the city with debt raised from LetterOne, the Luxembourg-based investment firm co-founded by Russian bankers Mikhail Fridman and Petr Aven, an examination of new corporate information by The Currency has found. Investors in the portfolio also include Irish companies and individuals including well-known business figures in Dublin and Co Cavan. Although their vehicle has disclosed details of just nine properties to date, its sophisticated corporate structure and the profile of its backers suggest it is on course to acquire many more. The company purchasing the individual apartments in…