IT TOOK five days, and no attempts to call Darrell Gene Simon, before his partner told his family he was missing.

Day one of a coronial inquest into the 46-year-old's death and disappearance also heard that Mr Simon asked a man involved with drugs to leave his property.

Mr Simon's partner Sharon Rowland last saw him when he kissed her goodbye prior to a bike ride.

It was a ride he never returned from.

His remains were found near a tree on a property he used to own 18 months later.

MISSING: Darrell Simon, of Plainlands.Photo Contributed
MISSING: Darrell Simon, of Plainlands.Photo Contributed Contributed

In a statement to police in 2016, Ms Rowland told officers she believed financial difficulties and conflicts with associates "just got too much for him and he just left without wanting to be found".

The inquest heard his bicycle was located in a dam about 40 metres from his remains just three months before.

Peter Boyce, representing Mr Simon's father Laurie, tendered phone records to the inquest that showed Ms Rowland never called or texted Darrell Simon for five days after he promised to be back home in a few hours.

It was only then that she told his father who reported Darrell missing to police.

Missing man Darrell Simon was last seen riding a bike like this. Photo Contributed
Missing man Darrell Simon was last seen riding a bike like this. Photo Contributed Contributed

That issue was explored extensively by Mr Boyce during cross-examination of a number of witnesses yesterday.

"She did nothing," he told the inquest.

The five-day hearing began with testimony from the man charged with leading the investigation into finding Darrell - Senior Constable Timothy Roberts.

The Criminal Investigation Branch officer told the inquest foul play was not considered during the probe to uncover how Darrell Simon died.

"There was no evidence held at that time or now to indicate that was the case," he said.

"My strong opinion is that he committed suicide not long after leaving the property.

"During the investigation it became evident that Mr Simon was in dire financial straights.

"In my position I have been involved in investigating 34 deaths that have been reported, 17 have been suicide and a large amount of them have been related to financial hardship or relationship breakdown."

Mr Boyce submitted that payments on land owned by Darrell Simon were all up to date at the time he vanished.

He also submitted that arguments with neighbours had been a source of considerable grief for Mr Simon and Ms Rowland. The inquest before Deputy State Coroner John Lock continues.

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