OFFICE rents in Central could increase by at least 10 per cent in the next six months, says property consultancy firm Vigers Hongkong. In a property market report, Vigers director Gareth Williams said the limited supply would force up rents for prime space. Rents in Central increased five per cent in the first quarter, bringing the average to about $44 per square foot a month, he said. Rents in some smaller offices in Central have surged by 15 per cent since August, with rates now more than $55 per sq ft in prime Central buildings. Rents in Wan Chai and Causeway Bay also firmed, averaging $34 per sq ft. On the overall market, Mr Williams said prices had shown resilience to the continuing Sino-British talks, and uncertainties surrounding the new airport and most-favoured-nation status for China. He said the property market was in sharp contrast to the stock market, which had been subject by enormous fluctuations in the recent months. Mr Williams said: ''The [property] market's recent performance makes it clear that the political factor is now an integral part of the Hongkong scene and has been largely discounted by most investors. ''Given the likelihood that politics will continue to play a key role in the next few years, this pragmatic approach by property investors is a welcome one.'' The report said that strata-title (floor by floor) sales of offices was ''healthy'', with prices in Lippo Centre reaching $6,900 per sq ft, Far East Finance Centre achieving $7,300 and Bank of America tower, $6,800. Office market yields remained low, in the region of 5.5 per cent to 6.5 per cent, but would begin to rise in the wake of rent increases, it said. In Tsim Sha Tsui, office prices have jumped to record levels, with a sea-view unit in East Ocean Centre selling for $7,500 per gross sq ft on the back of tight supply. In the luxury residential market, Mr Williams said rents had increased by five to 10 per cent in the last quarter on strong demand. Faced with limited supply and added demand from an increasing number of expatriates in Hongkong, rents for luxury accommodation could rise even further, he said. In contrast, the mass residential market has continued to stabilise, with some developments suffering price falls of five per cent over the quarter. ''The 70 per cent mortgage ceiling has had a debilitating effect on many would-be first-time buyers,'' Mr Williams said. He reiterated calls for a relaxation in mortgage financing rules to help genuine home buyers. ''A gradual, phased increase [in mortgage finance] to 75 per cent, and then 80 per cent, with the lending banks exercising judgement in treating each case according to its merits, would curtail speculation without punishing the genuine owner-occupation buyers,'' he said. According to Vigers, the sales market of retail properties was relatively active in the last quarter, dominated by several large transactions, most notable being the $2.22 billion sale of World Trade Centre building to Sun Hung Kai Properties. The industrial property market was fairly quiet, but interest seemed to be picking up. However, many investors in this sector were hesitant in the light of uncertainties over renewal of MFN, the report said.