Real estate activities Standard Industrial Classification (SIC) codes of UK-based importers and exporters 68100 - Buying and selling of own real estate (332569) 68201 - Renting and operating of Housing Association real estate (31516) 68202 - Letting and operating of conference and exhibition centres (2010) 68209 - Other letting and operating of own or leased real estate (525714) 68310 - Real estate agencies (54343) 68320 - Management of real estate on a fee or contract basis (152631)