"I was only 8 when it happened but he told me a guy came in on the day he opened here and said that he wanted a suit.
"Mick said to him, you don't need a suit - I just sold you one down the road.
"He said, you need the money more than me, and bought a suit."
He borrowed money to open the store, going "a wee bit out on a limb" and advertised heavily.
"I think they had budgeted to take about £400 on the first day. I remember my sister and I had the money in the satchel and tipped it out on the lounge floor and threw it up in the air before counting it. It was more than £800."
Mike worked in the shop from intermediate school, sweeping the shop floor before school and after school delivering the purchases and alterations in boxes stacked on the back of his bike, one hand steadying large loads on the pannier while he cycled one-handed in all weathers.
He was working in Vance Vivian Menswear in Wellington when he was 17 in 1966 but was called back into the family business after a senior staff member was killed in a car accident.
Ten years later his father was also in a car accident "and was lucky to survive".
"That's basically when I became the boss."
His father used a walking stick for the rest of his life and would visit regularly "and stir us up".
The tradition of gentle ribbing among staff continues at the Heretaunga St store, now managed by Mike's son Angus who has been in the business for 18 years.
Of the five menswear outlets in Hastings. Alexander's is the only other independent store. The others are Farmers, The Warehouse and Hallensteins.
He said historically Napier was perceived to be a tourist holiday destination and Hastings the business/retail centre.
"We had 21 menswear outlets in Hastings 25 years ago. It's been a bit of a change."
Many of the owner/operated menswear stores simply closed the door when it was time to retire, with the 1980s "very tough".
"If you want to make a lot of money you don't go into retail. There is no huge mark-up and high expenses - it is a way of life. The people that come in here are fantastic. In my 50 years I would say maybe once I have been tempted to ask a customer to leave."
The business has changed its footprint in the same building three times since 1957 and is now four times its original size, taking up the whole building on the corner of Nelson St and Heretaunga St West, which a family trust owns.
Its size is one of the reasons why it carries so much stock, with a suit department bigger than the original 1957 shop.
"It's a big shop and there is nothing worse than having a shop half empty."
With beards fashionable and trouser suspenders coming back into vogue, he says it's likely felt hats will again be popular.
Thomson's is the country's biggest stockist of Aertex shirts which he said were "a Hawke's Bay favourite ".
There were cheaper imitations available in other stores but he said they were not as good.
"You get what you pay for. If you buy a shirt for $45 it is going to give limited wear."
The difference was fabric and design.
"The Aertex shirts for example are made on the pattern they have been doing for years and years and years.
"They are very good value for money and they last. I have Aertex shirts that are still useful for work that I've had five or six years.
"We like to say if you buy an Aertex shirt you can wear it for five years for good and then it goes on to the farm. People say all the time they have shirts 10 or 15 years old that they wear on the farm."
"Country gentlemen" from as far as Dannevirke remain the mainstay of the business, with local professionals making up the balance.
He said men don't like shopping, himself included.
"A guy comes in and he says, right I want a pair of trousers, a shirt and a tie. You do it - you know me and you'll do a properly."
Customers' measurements were kept on record.
"Farmers ring me up and say, you know what I want."
Staff were told to guess customers' size before presenting an item to try on.
"If it's the right size they have confidence in you."
Wives visit when their husbands are at the Stortford Lodge stock sales and sometimes take clothes home on approval.
"Some people can't believe it. They say, you don't even know us so why are you letting me out without paying?"
They recently lost their only female staff member - an accounts administrator - but because of the decreasing number of accounts Angus Thomson now handles them.
"We used to charge a hell of a lot of goods up to customers but now most of them pay on eftpos or Farmlands card," Mike said.
While he has had a few slow debts "I've had no bad debts".
"There's a few we had to serve over the years but we've mainly got the money."
Clothing is sold "all over the world" via a brochure mailed-out, email marketing and a website.
"We send them to England, America and we even sell Australian socks to Australia."
Son Angus "is into that sort of stuff".
Mike said people had grown larger over the years "but they are starting to slim down a wee bit".
"I haven't."
He said the secret to Thomson's Suits' success was good value and good service, which has made it a destination store at the edge of Hastings' CBD.
"The old man always said you can't compete with the cheap stuff. You've got a have the quality - the best you can get at a price people can afford.
"Basically I think that's why we have survived, because we stuck to our knitting."
He has cut down his hours since having a few health problems in the past year, including a broken ankle, but still works up to six hours a day.
Thomson's Suits is celebrating his 50 years with the business, with photographic displays, a chance for a mystery weekend and, of course, a sale.
