Last August the phone began to ring at Vivian Patterson's Northwest home. Each time she answered, a different man introducing himself as a minister and a contractor would suggest coming out to provide cost estimates on various improvements to her home.

Each time, Patterson said she wasn't interested. Winter, she told the callers, was just around the corner and any extra money she had would go to pay the heating bill. They kept calling. Finally, Patterson relented and the "ministers" -- prepared estimates in hand -- arrived.

Today Patterson, a 64-year-old widow, faces bills totalling more than $2,000 for work she insists she never wanted done.

When the "ministers" encouraged her to sign the papers, Patterson recalled, they said her signature was needed only to guarantee the estimate for a year. She never expected the frantic call from her daughter, a few days later, telling her someone was outside dismantling the front steps.

Patterson's tale of financial woe was one of many aired by 40 disgruntled homeowners last week at a public hearing sponsored by the D.C oFfice of Consumer Protection. The hearing was called to consider possible ways of cracking down on home improvement firms that fail to do adequate work or engage in fraudulent practices.

The hearing was held Thursday at the District's 4th Precinct, 6000 Georgia Avenue NW.

Last year, 415 home improvement complaints were registered with the Office of Consumer Protection -- up 24 percent from the previous year.

In addition, home improvement complaints consistently involved large amounts of money. The average complaint involved large amounts of money. The average complaint involved from $7,000 to $10,000 according to the office's general counsel Frederick Goldberg.

Goldberg said there is no reason to expect the number of complaints to decline because more people now are renovating homes.

"Escalating real estate and mortgage rates," said Goldberg, "are forcing people to turn toward expanding and renovating existing homes rather than purchasing new homes."

As a result, Goldberg explained, numerous small home improvement companies are being formed in the District and inexperienced, incompetent and sometimes dishonest craftsmen are hitting the streets -- and unprepared homeowners, he said.

A contractor does not need a license to work unless he accepts money in advance on jobs exceeding $300.

"Not all home improvement firms in the District produce shoddy work or try to finagle people out of money," Goldberg said. But, he added, there are a surplus of firms who prey on an uneducated public.

Goldberg said his office receives a disproportionate number of complaints from women, the elderly and lower middle-class residents. "Anyone who is not really prepared to fend for themselves is a prime target," he said.

Two firms -- Family Construction, a home improvement company, and Red Start, a real estate company involved in selling renovated homes -- were mentioned several times at the hearing.

The Rev. William Bunum, president of Family Construction denied any wrongdong on the part of his company. "Out of 15 to 20 jobs, we've had only a few complaints. I am an honest man and a minister," he said. But, he added, "I am not Santa Claus. I can't give people what they don't pay for, and I've given everybody what they've paid for."

The consumer protection office said it is currently investigating three complaints lodged against Family Construction.

Red Start employes were unavailable for comment.

Greg Schaub, who described himself as a former employe of a Maryland home improvement construction firm and now a student at the University of Maryland, described the general selling tactics used by many companies.

Focusing on lower middle class neighborhoods, Schaub said, the firms enter a neighborhood under the pretence of looking for advertising exposure for their product. The salesmen -- or marketing directors, as they call themselves -- explain to a potential client that because they need immediate exposure in the area -- their boss is coming to town -- they would be willing to offer discounts of up to $1500 if the homeowner will sign that evening.

"The salesman would keep lowering the price," Schaub explained, "until the consumer would agree."

Schaub said it was not unusual for a salesman to make $3,000 in commission on a $10,000 deal.

Not all the homeowners at the hearing had contracted for renovation work.Some, like Leo Bosner, an auditor with the Federal Housing Administration, bought a house with a 2-year limited guarantee.

Two weeks ago, Bosner said he was informed by an independent investigator that $25,000 worth of improvements were required to make his $80,000 home livable.

The floors needed replacing: the new tile, now cracked and peeling, had been glued onto old unwashed tiles. The roof leaked: one meagre piece of tar paper covered the roof. And all the wood panelling and the porch had to go: they had been nailed onto rotten wood.

"I wasn't an ignorant buyer," Bosner said, "I took night classes and read various books on buying a home. And with the guarantee, I thought we were okay for at least a couple of years."

That guarantee is required under the District's Residential Real Property Excise Tax of 1978, a largely ineffectual and unimplemented law, Goldberg said.

Under the law, if a homeowner decides to sell a house within a year of purchase, he must offer the new purchaser a two-year guarantee or pay up to 93 percent of the profit in taxes.

Not only has the guarantee been ignored in practice, Goldberg said, but only $2,000 in revenue has been collected since the law came into force two years ago.

"The law," Goldberg said, "has been a total sham."

However, Goldberg told the homeowners that the consumer protection office, in conjunction with the D.C. police department and the U.S. attorney's office, is beginning to strengthen the enforcement of the law and has recommended four firms -- whose names he would not disclose -- to the District's corporation counsel for criminal prosecution.

He added the office was considering various ways of strengthening existing laws which he termed inadequate.

In the meantime, Goldberg warned that the best action a homeowner and a potential renovator can take is to become educated about the home improvement construction industry.

"Be wary of firms who come knocking on your door and offer you a seemingly low bid. Ask for references and call our office to see whether a complaint has been registered against the company," Goldberg advised.

Not everyone in the audience, however, was satisfied with Goldberg's plea for consumer education.

"I'm all for consumer education," said homeowner Leo Bonser, "but if I go home tonight while someone is trying to break into my house and I call the police who say they will send me a pamphlet so I can be better informed, its not going to do me a lot of good."

"There is a silent crime wave hitting our city," Bosner warned, "and if something isn't done about it now, in five years, our present situation is going to look like a picnic."