Sales of office space in Hong Kong are on the rise, but some industry experts are advising investors not to join the fray. Transactions for office properties rose 11 per cent last month from the previous month to 315 deals - the highest monthly total in the past 26 months, according to Centaline Property Agency. The total value of the transactions was HK$2.01 billion, an increase of 15 per cent over July's combined deal value. Ricacorp Properties research manager Patrick Chow Moon-kit said the outlook for prices of office space, especially in Central, was a continued rise due to supply shortage and Hong Kong's continued economic growth. Andrew Ness, executive director of CBRE, a research unit of CB Richard Ellis, said regardless of the profile of investors in office space - whether they were high-net-worth individuals or small and medium players - the Hong Kong office market remained highly attractive. However, some property consultants have expressed reservations about these views. 'Investment risk will be relatively higher as the market is entering the last phase of its upward cycle,' cautioned Simon Lo, head of Colliers International's research department. 'The continued surge in prices has pulled down rental yields. Unless you have holding power to wait for the next cycle or you find a very attractive deal, it is not rational to chase the market at this moment,' said Mr Lo. Nicholas Brooke, chairman of Professional Property Services, agreed. 'The office market is underpinned by strong rental demand. But capital values have risen to reflect this and we have seen significant yield compression,' Mr Brooke said. 'I think from a private investor's perspective, it is probably rather too late to enter this sector as most of the growth associated with this cycle has already occurred. 'Nonetheless, the institutions will, I believe, continue to pursue whole building acquisitions or buy into developments just because of the sheer amount of money allocated to investment in real estate in the region.' But, whichever view you take, supply shortages could decide matters for you, analysts say. Alva To, head of consultancy at DTZ's North Asia division, said it was difficult to source quality office properties for sale, as landlords were not eager to sell their properties because of limited supply.