The man accused of murdering author Helen Bailey twice tried to use power of attorney while she was missing in order to sell her flat, a court heard.
The body of the 51-year-old was found in a cesspit at her home in Royston, Hertfordshire, in July.
Her fiancé, Ian Stewart, 56, who denies murder, visited her solicitor in Ms Bailey's place on 11 April, the day she went missing, to discuss the sale.
He claimed she was "too unwell" to attend, St Albans Crown Court was told.
The Northumberland-born author of the Electra Brown series for teenagers, was last seen alive on 11 April.
Mr Stewart reported her missing on 14 April. Her body, together with that of her dog was found in the excrement-filled septic tank beneath a garage three months later.
The prosecution alleges Mr Stewart murdered his partner, who was worth an estimated £4m, for her money.
Ms Bailey had been due to meet her solicitor Timothy Penn to discuss the sale of her £185,000 Gateshead flat on the afternoon of 11 April.
Instead, Mr Stewart attended saying his partner was unwell, Mr Penn told the jury.
While she was missing, Mr Stewart tried to push the sale through and was "not at all pleased" by the lack of progress, the solicitor said.
Mr Penn told the jury during one phone call Mr Stewart said: "You probably know that Helen is missing and I'm wondering if you can carry on with this transaction in the meantime."
Mr Penn said: "I said effectively no. He talked about a power of attorney and I said in these circumstances we would want to hear from Helen."
Earlier in the trial, the court heard Mr Stewart had been given power of attorney alongside Ms Bailey's brother John in 2015, allowing him to control her affairs should she become unfit to administer them.
Mr Stewart's sons Jamie and Oliver Stewart were also in court to give evidence on the fifth day of the trial.
Following Mr Stewart's arrest, the court heard he told his son Oliver that two men, named as Nick and Joe, had repeatedly showed up at the home to demand paperwork.
He claimed he had been assaulted by the men and on one occasion was given a mobile phone and forced to follow certain instructions.
Oliver Stewart, 21, told the court: "When he was telling me about these people, I could see that he was not joking, I could see the fear.
"Purely by him telling me that, that was the road I can see he was going down."
When asked by prosecutor Stuart Trimmer QC "what road was that?", Mr Stewart replied: "I concluded they were involved in taking Helen because of the way he was telling me - there was fear in his face, he was not just joking about this."
Jamie Stewart said on the day of the alleged killing, his father had travelled to Cambridge to watch him in a bowls match.
Later that evening the pair had a Chinese takeaway at their Royston home.
Jamie Stewart told the court, when he got home from work the following day - 12 April - his father told him Ms Bailey had left him a note saying she had gone to Broadstairs "to get some time for herself".
"Throughout that week, he began to get visibly more stressed out. He was spending a lot more time with myself and my brother and wanting to be around us," he said.
Several days later his father told Jamie he had reported Ms Bailey missing.
Ian Stewart denies charges of murder, preventing a lawful burial, fraud and three counts of perverting the course of justice.
The trial continues.