The outgoing owner of Enterprise Upholstery, in Rankeilor St, said he had put his "heart and soul" into the now-sold business.
"My first week of business, I had nothing to do except for my sister-in-law’s sofas because she said ‘you might as well do something’," Mr Williamson said.
"And now, I employ four and myself.
"I'm leaving it in a very, very good position."
Mr Williamson is turning 65 in August and said he was "a little nervous" but excited about starting this new chapter of his life.
As of April 1, upholsterer Sam Johnston would take up the mantle of owner — whom Mr Williamson said was "like a son to me".
He confirmed the change in ownership was not in fact a sneaky April Fool’s joke.
"That thought had crossed my mind, but no, no," he said.
"Papers are signed."
At this stage, Mr Williamson was trying not to make any plans for his retirement.
He had already been planning and organising for so long, he said.
"I've been go, go, go ever since I started.
"It's time for a rest."
His father Sam Williamson founded the business more than 60 years ago; Mr Williamson said he started working for him in 1983 before taking over ownership in 2004.
Projects over his career ranged from the corporate lounge of Forsyth Barr Stadium and the booth seating at the Law Courts Hotel to a "horse phantom" — an imitation mare used for semen collection on a stud farm.
On the business’ agenda yesterday were curved ottomans, a dozen metal-framed chairs, a valance for an antique couch and a truck seat "for a guy who got failed on his warrant," Mr Williamson said.
"There's such a wide variety of things here, it's absolutely amazing," he said.
"No day is the same."
Mr Johnston, who had a decade of experience at the business under his belt himself, said taking the reins was a good opportunity.
At age 27, he was on the "younger side" of being a business owner, he said.
Upholstery was a niche market with few working in it.
"There’s so much work out there at the moment, honestly, it doesn't feel like it's going to slow down anytime soon."
