The former Livingston FC chairman. who made his name in telecoms more than a decade ago, has grown Creditfix from 75 staff in 2010 to 265 now, and the 35 roles at Manchester-based Simple Debt Solutions will be replaced by five new jobs in Glasgow.
Mr Flynn said he expected Creditfix to turn over £31m this year, a 28% rise on last year, with 16,000 clients under management. He said growth had been driven by a culture of being "empathetic to our clients' needs at a difficult financial time in their lives".
He added: "We are delighted to have completed this deal as it increases our market share and grows our business within a sector that is contracting.
"We are a very ambitious business and intend to make more acquisitions of this nature over the next 18 months."
On whether the man who chaired Livingston FC from 2004 to 2008 would ever consider a return to that arena, he said: "I have been too close to insolvency to ever go back to football."
The deal goes against the trend of English insolvency firms making inroads into the Scottish market, where Creditfix now has only 15% of its business.
Now the entrepreneur is poised to launch a new business offering credit rating repair to people emerging from an insolvency process. He said: "It is a great opportunity, it will be a separate company based here in Glasgow, and I am now recruiting for chief executive for that business."
Mr Flynn previously ran businesses for Compaq and Newbridge Networks, and then Ericsson, before leaving its high-flying Damovo subsidiary in Glasgow in 2003 after it was bought by Apax Partners.
He had made his fortune and become a football chairman before setting up sub-prime consumer lender Smarter Loans.
Then in 2007 he picked up Creditfix, intending to build a parallel insolvency practice offering solutions such as equity release and financial restructuring.
On the timing of the deal, he says: "It was Irish luck. I bought the restructuring business, then the lending business collapsed... it was a very tough challenge for me in terms of one business crashing and the other business growing."
But, he says, when it comes to helping Creditfix's corporate clients deal with the issues of a collapsing business "I know exactly what it means".
Mr Flynn said Scotland was years behind England in making its principal insolvency product, Protected Trust Deeds, as efficient and creditor-friendly as the English Individual Voluntary Arrangement (IVA). This month trust deeds have at last been tightened up by extending the debtor's repayment period from three to four years, helping to narrow margins further in a formerly lucrative market.
Mr Flynn commented: "In Scotland they have totally disregarded creditors. In England you have to deliver dividends to the creditors within a year."
He said guaranteeing a creditor return from trust deeds, as Creditfix did, was almost unknown, but the Scottish market was at last changing.
"I expect to see a lot of consolidation in the industry North of the Border because, quite frankly, some of them just don't have the technical infrastructure. You have to pay dividends, they should have been doing it before, I think we will see the strong survive and thrive in Scotland, and within a year there will be six companies taking 80% of the volume instead of 20%."
Mr Flynn says he was approached by a headhunter in 2011 to run a large telecoms company. "I said no thank you, you would probably end up firing me after six months."
The Irishman's Lionheart consortium stepped in to take control of Livingston FC in 2004 after the club was put into administration by Bank of Scotland with debts of £7.2m, after what the club's website calls a reign of financial mismanagement under "discredited" chairman Dominic Keane.
But Mr Flynn's controversial four-year tenure saw the club relegated from the SPL in 2006, and in 2008 he sold his shareholding to an Italian consortium led by Angelo Massone - whose one-year reign ended when Livingston went into administration for a second time in 2009. The club is currently sixth in the SPFL Championship.