Flatmate Sharlene Clark said she knew straight away it would be Mr Oliver as soon as she learned that a body had been discovered in the harbour.
"I'm so happy that we can finally say our proper goodbyes...These past 19 days have been some of the hardest I have been through in my life," she said.
"Watching Simon's car being pulled from the river, and then waiting in anticipation for him to be found has been the worst couple of weeks I have ever gone through," Ms Clarke said.
Head tenant Conrad Field agreed.
"It's been a very painful three weeks...Finally being able to put to rest the final page of Simon's life-story is really sad but a huge relief, not just for us but for his family."
Mr Field said it was only after Mr Oliver moved in as flatmate about six months ago, that they learned that they had attended the same school - Bay of Islands College.
In April 2006 Mr Oliver lost the lower part of his right arm in an industrial workplace accident in Tauranga.
His long-standing friend Andrew Colcord said not long after the accident Mr Oliver returned to live in the Whangarei district.
"That's where I first met Simon and we seem to click straight away...I liked Simon, he was cool. He was bit of character, with a wry sense of humour," he said.
"I think he was a little bit lost after the accident and he was trying to find himself again. Simon had seen a lot and been through a lot in his life, and he found it very hard to accept being disabled," Mr Colcord said.
"Simon was a highly talented diver, and also had his skipper's ticket. He was really passionate fisherman and was keen to start up his own fishing charter boat business."
Flatmate Gina Hunt also paid tribute to Mr Oliver's sense of humour, saying the house was often filled with laughter when he was arround.
"Simon's humour was often quite black. Sometime his jokes hit the mark, other times they fell flat, and we used to give him a lot of stick about it.
"I used to say to Simon that he had more spare prosthetic arms than an octopus, and he used laughed his head off," she said.
His friends also described Mr Oliver as "highly intelligent" - a "really skilled mathematician" and electronics whiz, particularly when it came to repairing computers.
"Today [April 20] would have been Simon's 54th birthday, so we are going to hold a pool tournament in his honour at the Settlers' Bar in Tauranga," Ms Clarke said. "It was Simon's local and he was well known by lots of the patrons."