"I asked my husband what he thought," she says, "and he said I might get enough money to get a deposit for a house." She persuaded a local builder in north London to let her have a desk and a phone. Her business partner would supply the hours and she - because of her domestic position - the expertise.
A few years later, the partner left the business and Ms Weitz turned what is now FDS International into a limited company. It employs 30 people full time and about 150 part time, and in its last financial year saw turnover pass pounds 4m.
FDS is highly successful, with BT and British Gas among its longstanding customers. But she insists that at a time when companies are talking globalisation, remaining independent is a struggle.
"Unemployable" by her own admission, in that she is "very bossy, very ambitious", she enjoys the freedom that running her own business provides. But it requires adaptability, reinvention and a fair amount of "ducking and diving" to keep customers and clients happy, while at the same time staying true to core values.
Last year the company, which has a significant proportion of women at the top, celebrated its 25th anniversary. It is now planning a survey to find other owner-managed businesses that have lasted a similar course.
Ms Weitz's enthusiasm stems from a belief that the success of businesses like hers is vital to the survival of commerce as we know it. Business advisers and politicians increasingly recognise the importance to the economy of such enterprises. The giant mergers announced on an almost daily basis are bad for employees because they generally lead to loss of jobs, and bad for consumers because they reduce choice, she adds.
Her plea on behalf of the small and medium-sized enterprise sector comes as the Independent on Sunday, in association with Price Waterhouse, the accountancy firm, launches its sixth annual listing of the fastest-growing private companies in Britain.
The Independent 100, published in the spring, is based on annual compound sales growth over the five years to 30 June, 1997. In addition, there is recognition for theachievements of companies that continue to expand quickly even though they have reached a certain size, through the Middle Market 50 listing. To qualify, companies must have sales of at least pounds 5m in the financial year to 30 June, 1993 and more than 150 employees in the year to 30 June, 1997.
To give an idea of the performance that will qualify you for inclusion, it should be remembered that each of the top three companies in last year's Independent 100 achieved average annual sales growth over the five years of more than 100 per cent, while even for the 100th company the figure was 33.5 per cent. In the middle market the top-placed company, a mobile phone business, Caudwell Subsidiary Holdings, achieved average annual sales growth of more than 75 per cent. For the 50th company the figure was 25 per cent.
Pointing out that over the past seven years the listings had "become established as a premier forum of UK fast-growth emerging companies", Nigel Crockford, PW corporate finance partner responsible for the listing, said: "The Independent 100 and Middle Market 50 listings identify the star performers in the UK private-company sector, an area of the economy so vital for the creation of wealth, employment and economic growth."
If you think your company stands comparison with such businesses, contact Julie Harwood at Price Waterhouse for an application form. The address for application forms and completed entries is Independent 100, Prince Waterhouse, Southwark Towers, 32 London Bridge Street, London SE1 9SY. Entries must be returned by Friday, 27 February.