Flanked by his wife Margaret and his lawyer Peter O'Brien, Spedding on Monday said he had told police and a NSW coroner everything he could to help them find William.

The three-year-old went missing from his foster grandmother's home in Kendall, on NSW's mid-north coast, about 10.15am on September 12, 2014.

Mr Spedding, a whitegoods repairman who visited the home three days earlier to fix a washing machine, has always vehemently denied any involvement.

"Obviously the police, and the investigation and the media interest in mine and Margaret's movements have had a devastating impact on my life, my family's life and livelihood," he told reporters outside the NSW Coroners Court.

"I thank my family, friends and legal team in getting me through this.

"I know what I've been through is nothing compared to what William's family are going through now."

The inquest on Monday heard that on the day William went missing, Mr Spedding and his wife met for coffee about 9.30am in Laurieton, a 15-minute drive from Kendall.

They had a coffee and shared some food before walking across the road for the local school's assembly, where a child they cared for was to receive an award.

A receipt shown to the inquest showed the Speddings' joint account was used to purchase a ham and cheese croissant, a citrus tart and two large cappuccinos about 9.45am.

But detectives remained interested in their movements and in January 2015 they searched Mr Spedding's Bonny Hills home and his Laurieton business.

Items were taken for testing and the home's septic tank was drained, but no forensic evidence was found linking Mr Spedding to William's disappearance.

Two days after the raid, a neighbour of Mr Spedding made a statement to police about "definitely" seeing the tradesman's van emerge from bush 20km from Kendall on the night of William's disappearance.

That statement came after he made a verbal report in September 2014.

But at the inquest on Friday, a backtracking Dean Pollard said the van he saw only "looked like" Mr Spedding's van and then - after viewing a picture of the repairman's van - admitted the two van's couldn't be the same.

The inquest on Monday was told Ms Spedding couldn't believe it when police knocked on her door and began raiding the family home.

"We were in shock," she told detectives in a video filmed a month after the raid.

"We couldn't believe this was happening to us."

Mr Spedding told the inquest he first learnt William was missing the night of the boy's disappearance when an alert flashed up on the nightly news.

"Our ears pricked up and we said, 'that's awful close to home' and we really tuned in," he said.

But as his client's surname wasn't Tyrrell, he said he didn't realise he'd visited the home days before William's disappearance until a police officer spoke to him on September 15.

Mr Spedding has already begun defamation action against at least two media outlets over their reporting of him.

He is considering further action, his solicitor says.

"First, we've got to get through this inquest," Mr O'Brien told reporters on Monday.

"This has been a massive ordeal for everyone."

No person has ever been charged over William's disappearance. The inquest is due to resume on Wednesday.

Australian Associated Press