Latimer was murdered on September 30, 2018, in Te Haroto, a settlement 55km to 60km along the Napier-Taupo highway, from Napier.
The summary of facts stated the two offenders lured Latimer to the address, before beating him and telling him to dig his own grave.
Latimer was known to the offenders through the Hawke's Bay drug world but had not been in contact with them since an aggravated robbery in January 2017.
The acquaintance texted Latimer asking him to come to the address and supply drugs, with Latimer unaware the offenders were there.
They attacked Latimer, beating him around the head, before dragging him to the back of the property, where he was beaten with a shovel. The shovel was then thrown at Latimer, and he was told to dig his own grave, before the offenders began to dig one. Lothian then stabbed Latimer multiple times, including once to the throat.
He was buried, and discovered on October 6, 2018.
An autopsy confirmed Latimer died from stab wounds to the chest and abdomen.
"Your limited dealings with Mr Latimer may only have been in the context of drug dealing, but he had another life in a close-knit family where he gave considerable love and support, and your brutal killing of him was entirely unprovoked."
Latimer's sister-in-law, Megan Latimer, read an emotional victim impact statement, saying on the night of the murder, the entire family had slept well, not knowing what was happening.
"Now I don't sleep well."
She said she naively thought such a "heinous and insidious" crime was something her family would only read about, not experience.
Her future children would never know their "Uncle Alex", and her happy memories of him had been ruined by the way he had died, she told the offenders.
Prosecutor Steve Manning said Latimer knew he was going to die well before it happened.
He said Lothian led the attack, but Webby went along with it.
Lawyer, Roger Philip, said Lothian acknowledged he was wrong.
Leo Lafferty, who appeared on behalf of Webby, said Webby was not the leader but was there, and did not deny that.
Detective Sergeant Darren Pritchard said the sentencing bought some degree of closure to Latimer's family.
"The death of Mr Latimer was a needless tragedy that will forever leave a void."
Both men also pleaded guilty to aggravated robbery and arson, Lothian to a charge of reckless driving and Webby to perverting the course of justice.
SOME OF NZ'S 20-YEAR+ SENTENCES:
William Bell
Bell became one of the most notorious murderers in New Zealand history when he callously gunned down William Absolum, 63, Mary Hobson, 44, and Wayne Johnson, 56, during a robbery at the RSA on December 8 2001.
He also shot Susan Couch, who worked part time doing the club's accounts.
She survived - just.
Bell left the mother-of-one for dead with broken arms and severe head injuries that caused a stroke.
She lost about 80 per cent of her blood and ambulance officers later said she came as close to dying as she could get.
Bell was jailed for life, with a minimum non-parole period of 33 years initially.
The non-parole period was reduced to 30 years on appeal. He was also sentenced to 13 years' imprisonment for attempted murder and a concurrent 12 years for aggravated robbery.
Bruce Howse
Howse was sentenced to 28 years non-parole on his life sentence for the murders of his stepdaughters Saliel Aplin and Olympia Jetson in their Masterton sleepout on December 4, 2001.
Justice Lowell Goddard said she unequivocally accepted Howse was molesting the girls and that was his motive for the killings.
Howse was found guilty of the murder of the girls exactly a year after the sisters were stabbed to death in their beds.
Antoine Dixon
Dixon was given life sentence with a 20-year, non-parole term for the murder of James Te Aute in Auckland and an enraged sword attack on Simonne Butler and Renee Gunbie at Pipiroa near Thames in January, 2003.
Dixon died in Auckland Prison the day before he was due to be sentenced for the murder.
Mark Lundy
Christine Lundy, 38, and her daughter Amber, 7, were murdered in their Palmerston North home in August 2000.
A jury found Mark Lundy guilty of the murders of his wife and child after a High Court trial and he was sentenced to 20 years non-parole.
In 2015 Lundy was granted a retrial.
The jury, which deliberated for 16 hours over more than two days, returned unanimous guilty verdicts for both murders.
Justice Simon France sentenced Lundy immediately and reimposed the previous penalty after he was found guilty of the double murder in 2002: life imprisonment with a minimum non-parole period of 20 years.