"Ros reckons you will be reading this in the year 2020. I built the wall, and I reckon closer to 2060," the letter said, proving he was a little ambitious about the date.
Greg and Roslyn bought the house in 1987 for just $170,000, and had to gut it and renovate everything but the shell to make it liveable.
"Ros is pregnant and because she is the inquisitive type, we know we are expecting a son," a clearly excited Greg wrote in the letter.
The letter is bittersweet, because the couple welcomed a baby boy named Mark in August 1995, but Roslyn tragically died two years later from breast cancer, Greg told Fairfax.
Greg Wilkinson with his late wife Roslyn Green on their wedding day. Photo / Facebook
"I feel quiet emotional having seen it. All that water under the bridge for me and the world. My beautiful Ros looking back at me from the past," he said.
Back in 1995, Greg predicted in his letter that Islam would plunge large parts of the globe into a "holy war" that it will continue for a long time until "both sides realise that if this is what their god wants, then there probably isn't one after all".
He also wrote that China would become a world economic superpower, and said if they ever decide they'd like more space, Australia could be a target.
"Our only means of defence is understanding," he said.
The letter was written using Word for Windows V5.0 on a Laptop with 8mb of RAM.
"This gear is near the top of the PC scale right now," he wrote.
"The big deal at the moment is the Internet. This is just exploding and every man and his dog wants to 'surf' the Internet. Please tell me this expression has now died."
He added that he gets around in an Isuzu four-wheel drive, "but I sincerely hope that by the time you read this, there is some other form of nonpolluting form of transport".
Back in 1995, a loaf of bread cost $2.25, a case of Carlton Cold was just $24.95, and one litre of fuel cost only 68 cents - a price that seems unimaginable today.
"Hope I haven't made the future look too bleak, but if one focuses on the problems of today, they would probably seem bleaker. We're however, having a ball," he said.
"We hope you enjoy living here as we did".
Facebook users were seriously impressed by his insights.
"Some accurate foresight there!" wrote Ben Frazer.
"I was one year old when this was done it's always interesting to see how times change," wrote Trent Schaffer.
"He wasn't far off the money there. Hey Greg, what's Tuesday's lotto numbers?" asked James Galdal.
