But what he didn't expect was to be so captivated by jewellery and ornaments formerly belonging to the Dowager Duchess of Devonshire, Deborah Cavendish, that he paid more than 100 times the estimated price for some of them – and now can't bring himself to sell the items on.
Mr Jepson, from South Milford, near Leeds, said: "The Dowager Duchess is a lady I greatly admire. I am very glad to have secured some of her possessions and shall greatly treasure them.
"The brooch is one of those unique pieces that I've never seen before and never will again."
He added: "The Chatsworth sale was a unique occasion – the only other house in Britain I can think of that would have a bigger sale than this would be the attics of Windsor Castle."
While Mr Jepson purchased a number of items that will now be sold on through his Sherburn in Elmet-based company, the Dowager Duchess's mirror, pill box and Italian brooch will remain in his own family to be passed on to generations to come.
One of his favourite purchases was the turn-of-the-century enamel brooch for which he paid a huge 8,500 – more than 100 times the pre-sale estimate.
The 52-year-old said: "The brooch, pill box and 19th century mirror look rather nice as a collection together. The brooch has a lovely inscription which reads 'L'amour en fait le lien' – or 'Love binds together'.
"I don't know who the Dowager Duchess got the brooch from, but I'm intending to write to her to try and find out more about it.
"The items are particularly special because they're pieces connected with someone that has figured prominently in British and international life."
Father-of-two Mr Jepson will be displaying the brooch at home alongside the pill box, which was made in France, and the dressing mirror.
Items he's planning to sell on, meanwhile, include Meissen decanters, cups and saucers, an 18th-century ginger jar and a bottle of Chateau Cheval Blanc wine from 1959.
He said: "I picked a sample of things that I thought people would be interested in. Some people come along to sales and know they want to buy something, but they don't know what.
"The wine is very valuable but, ultimately, it will be drunk as it won't taste wonderful forever."The Chatsworth sale, Mr Jepson said, was of particular interest owing to its rarity.
The event also caught the attention of a number of celebrity guests – although rumours that Jerry Hall was spotted browsing the marquees remain unconfirmed – and, throughout the auction, private helicopters flew in and out of the estate grounds as the rich and famous dropped in for a spot of shopping.
"It's very unlikely that there'll be another sale at Chatsworth in the near to mid future due to the amount of work that has to go into such things", Mr Jepson said. "It took Sothebys about two years to amass everything, get it catalogued and get it researched. It's a tremendous undertaking, even for an organisation like Sothebys.
"When I saw that the attic sale was coming up I thought that I'd go and have a look on the viewing days, to see the quality that was there.
"I found that there were lots of things that caught my eye. One lot of books was of interest because I noticed that there was a handwritten inscription by the author, who gave the book to one of the Dukes of Devonshire.
"What I tend to look for is something that connects an item to a person.
"Inscriptions, for example, can give extra provenance to an item."
Another item that appealed to Mr Jepson was a table centrepiece featuring cherubs.
He said: "This sort of thing was very fashionable and cutting-edge back in the 18th and early 19th centuries. People wanted to decorate their houses with things that were fairly
Those interested in getting their hands on a possible goldmine or a priceless piece of history, Mr Jepson said, shouldn't have any fear about going along to an auction themselves.
"The odd scratch of the nose isn't going to be taken as a bid", he said.
"People really should try it as you can get a lot of good-value items. At the moment, Victorian brown furniture is out of fashion so sells very cheaply.
"At the moment, you can pay a lot less for a lovely Victorian breakfast table, for example, than you'd pay for a cheap mass-produced table in one of the big stores.
"Like everything else, antiques is a fashion industry, and some things become the mood of the moment."