A former property agent has claimed trial to allegedly misappropriating cheques worth more than half a million dollars that were handed to him by an elderly client who was blind in one eye.

Terence Yan Khek Yong, 29, was with HSR International Realtors when he allegedly committed criminal breach of trust of five cheques totalling $559,200 given by Mr Chan Kee Kok, then 89, between Sept 25 and Oct 7, 2010.

The payments were supposedly for the purchase of a unit at Eastpoint Green at Simei Street 3.

Yan, who is now a businessman, is also accused of instigating Mr Chan's Indonesian maid, Ms Sarina, then 25, to give false evidence to the police to the effect that her employer had told Yan to spend $200,000 in a cheque issued to him.

Mr Chan, who was blind in his right eye and had poor vision in the other, died a year ago. At the time of the alleged offences, he was a wheelchair user and living with his intellectually-impaired daughter, Ms Chan Liu See, who is in her 60s.

The court heard that Mr Chan had engaged Yan to sell his apartment at The Modena, Simei Street 4, where he was living with his daughter, and to buy a smaller apartment to live in.

Mr Chan's condominium was sold for $1.05 million in November 2010. Three months before the sale's completion, Yan had received his commission.

In its opening address, the prosecution said Yan arranged the purchase of a smaller apartment for Mr Chan and his daughter at Eastpoint Green, Simei Street 3, at $740,000, which was to be registered under Ms Chan's name.

The payment for the property was to be in cash. Mr Chan paid $55,426 for Yan's services and commission.

Deputy Public Prosecutors Leong Wing Tuck and Nicholas Tan said they will show evidence that Yan then received five further cheques from Mr Chan after he had received his commissions in full.

None of these cheques was intended for the benefit of Yan.

The prosecutors allege that Mr Chan was led to believe that the five cheque payments were required for the purchase of the Eastpoint Green apartment.

The offences came to light when Yan tried to encash a $200,000 POSB cheque at DBS Bank's White Sands branch on Oct 12 that year.

Two days later, Mr Simon Quek, then DBS compliance manager, and two colleagues visited Mr Chan at his home and called the police to inform them that Mr Chan might have been cheated.

The trial continues.

The maximum penalty for criminal breach of trust as an agent is life imprisonment or a jail term of up to 20 years and a fine.