After Lincoln, he had a selection of jobs offered and chose to work for Mair Wool in Christchurch, a business that was essentially an auction appraiser.
Then, in 1986, he bought an existing wool-buying business in Oamaru and moved south.
He had spent two years driving heavy machinery in Twizel, with the hydro development, in the late 1970s and had got to know some North Otago folk, so it was not entirely unfamiliar.
At that stage, the business was based in Tyne St but it later needed more space and Catto Wool moved into Harbour St, in the heart of the town's historic precinct, in 1991.
But back then, it was not the bustling attraction that it later became - "no one cared about it back then" - and he initially took half the building, then three-quarters and then the entire space.
Later, more space was required and premises in Tyne St were leased.
The last six or seven years had been particularly tough and, while Catto said he always tried to have a glass-half-full approach rather than a negative one, it was getting very difficult to do that.
But he remained hopeful that the industry would come right.
"I'm always looking for hope at the other end. Surely there's light at the end of the horizon now."
Known for his own woollen attire, Catto said one of his pet beefs was farmers who did not believe in their own industry, whether that was wearing synthetic - or plastic - clothing, or laying synthetic carpets in their homes.
"When that starts happening, you may as well throw in the towel. You have to believe in your own products," he said.
Catto's work covered a large area, from the top of the Styx to Waikouaiti, the Lindis Pass, Twizel, the top of the Hakataramea Valley and Waimate.
During the heyday, it was not unusual to do 14-hour days and he had the same routines; breakfast used to be a mutton pie at McGregors tearooms in Palmerston; latterly it had been at Vanessa's Cottage Cafe in Hampden.
In the 2021-22 season, Beef + Lamb New Zealand estimates that shearing expenses will account for 99 per cent of wool revenue for the average farmer compared with 36 per cent in the 2016-17 season (before the downturn in strong wool demand and prices).