NOW THAT THE HOUSE has decided there will be no Consumer Protection Agency, we're still left to our own wits in coping with the world of commerce. This may not be a bad thing.The typewriter and the personal encounter, I have found, are frequently mightier than the government agency - and invariably quicker.

I was 11 years old, my father tells me, when I dashed off a sharp note to the president of the Daisy Air Rifle Co. lamenting the deficiencies of my BB gun. I have no memory of whether I received any satisfaction from Daisy, but the event marks the beginning of an informal career as the champion of my favorite consumer - me. Since then, I have won some battles against the free enterprise system and lost many more. But, in the process, I have formulated and refined a variety of theories that seem to have general application for the beleaguered consumer.

1 Challenge the Giants and the Dwarfs, but Beware of the Medium-Sized.

The most satisfying moments in a personal consumer crusade occur when one energizes an industrial Goliath, such as the Allstate Insurance Co.

Fifteen years ago, after a surly local agent had refused me automobile insurance and offered no explanation, I sent Allstate's chairman a registered letter describing my driving record in excruciating detail. Within two weeks, platoons of Good Hands people were begging me to entrust my car to them. The key to my success was the target of my appeal: In a vast corporation, everything trickles down; nothing flows up. To deal with the local or regional manager is to invite profound depression.

Just as a large national company is normally mindful of its corporate image, so is a small neighborhood enterprise concerned about its local repute. My local cleaner, for example, muttered only briefly before paying me for my favorite tie after it was swallowed up by his mangle. And I got at least a draw with my local plumber when he created three new leaking pipes while installing a water heater. He didn't repair the pipes, but I didn't pay the full cost of the water heater, and his enthusiasm for sending dunning notices eventually waned.

It is the annoymous, medium-sized manufacturer, with no national reputation and no proximity to his customers, who can be the bane of the consumer's existence.

In 1976, for instance, I tried to capitalize on a five-year guarantee on the covering of a recently purchased attache case. Though I wrote directly to the president of the firm, and twice mailed the torn and frayed case from Washington to Chicago (at my expense). I received no satisfaction beyond two dabs of glue on the tearms and cryptic messages from an unsympathetic repairman. Absolutely nothing could shake this technician's conviction that I was secretly pummeling my attache case with sharp objects and had thereby voided the guarantee.

While carrying my belongings between home and office in a manila envelope for a period of two months, I had more than enough time to reflect on my complete lack of leverage. Clearly, there was (a) little repeat business in attache cases, (b) no national image to damage, and (c) no danger that I would spend $100 to fly to Chicago to argue over a $26 purchase - all of which leads logically to my next theory.

2 Be Persistent, but Know When to Cut Your Losses.

Obviously, any detached reader of my correspondence with the attache case factory would have advised an early retreat. This is the tactic I employed in a dispute over tuition payments to a school attended by one of my children. Recognizing the right of the school to expel my child for any reason, including whimsy, I quickly withdrew from that one-sided contest after my initial pleas were ignored. The potential return simply did not justify the risks.

On the other hand, I did not hesitate to badger the Ford Motor Co. until it had compensated me satisfactorily for the indignities heaped upon my Pinto by one of its dealer repair shops. Importuning a car manufacturer is a risk-free endeavor, and Ford presumably has an interest in its repute and in repeat business.

3 Intimate Clout, but Do Not Lie.

An individual who is, say, the local prosecutor obviously would be wise to use his professional stationery when reminding a commercial establishment of its failings, although it is a nice touch to state that one is writing as a private citizen. In general, trying to gain an initial edge is nothing more than simple prudence.

Idle threats are counterproductive, however, and nearly all threats from a single individual are idle when subjected to serious scrutiny. Lying is a particularly bad idea, since even if the ploy is successful, years of unnecessary worry will afflict the normal, law-abiding citizen. Having at the age of 13 invented the firm of Coogan, Butterworth, Washwelton & Fink to hint at legal action on my behalf, I continue to hope that the statute of limitations will expire on this youthful fraud.

4 Watch for the Whipsaw (or Catch-22).

Occasionally, even the most vigilant consumer can be ensnared by circumstances that make the merits of his case irrevelant. Anticipation and avoidance are the only remedies.

Two years ago, I purchased a mildly modish suit from a clothing store which does no alterations, the salesman having alleged that a few tucks here and there would make it absolutely perfect. I then took it to a tailor who opearates under the same roof, but is, in fact, an independent entrepreneur. After a bit of reckless cutting, the tailor produced a butchered garment that cut off my circulation from navel to mid-thigh. When I protested, the tailor said that a modish suit should not have been sold to someone with a body like mine (41 regular); the salesman countered that the suit was perfect until I placed it in the hands of the clumsy tailor. Ultimately the president of the clothing firm provided me with a new suit, but only his enlightened attitude prevented a permanent stalemate.

5 Nothing Ventured, Nothing Gained.

Personal consumer advocacy is Russian roulette. Though it is possible to increase one's odds, it is impossible to state with certainty which appeals will be heeded and which ignored. Therefore, it is imperative that the initial complaint be by registered mail.

While my literary labors yielded zero attache cases, a much less extensive effort brought me three new tennis rackets in three successive months, all of them eventually reduced to kindling by mis-hit overheads. (I have switched to aluminum).

Insurance companies are astonishingly unpredictable. I received nothing when a gale swept away several of the trees in my yard; the company argued that no "structures" were damaged. Yet the same company insisted on compensating me for the cost of painting a garage ceiling that was water-spotted by a leaking shower drain on the floor above. It made no difference that the spots had dried and the ceiling was previously unpainted.

6 Carbon Everybody.

The Russian roulette factor obtains here as well. Five carbons may be blanks and the sixth a direct hit. Politicians, the media, state and local agencies, better business bureaus - anyone with even a peripheral interest, should be included. Occasionally, the carbon list spurs competition among the recipients, to the great advantage of the consumer.

7 Be Sincere, Factual and Readable, but Not Sarcastic or Contemptuous.

It is well worth noting that the company receiving a consumer appeal can, in most instances, dismiss it peremptorily without any significant economic consequences. Regardless of the legitimacy of a grievance, the consumer must appear rational and persuasive or risk consignment to the company's "crank" file.

Pejorative statements on American capitalizm, adhominem assaults and sarcasm may fulfill the needs of the consumer's psyche, but they rarely help his pocketbook. A bit of urbane humor may be a net plus, however, particularly after the initial correspondence has established a comfortable rapport.

8 Overwhelm Them With Details.

The best letters are those which include times, dates, places, names of offending parties, copies of sales slips or canceled checks and any other evidence that can convey the image of an injured but temperate consumer. My letter to Ford on the Pinto was a massively documented, four-day chronology which, while tedious in parts, yielded results.

It also is often useful to volunteer mildly (but not seriously) damaging information to reinforce the appearance [WORD ILLEGIBLE] veracity. My letter to Allstate, for example, described at some length an unreported accident that had occurred five years earlier when my car was sideswiped by a 1929 Model A piloted by a septuagenarian.

9 Preserve Every Shred of Evidence.

In addition to the various forms of paper that can be enclosed with a letter, the broken appliance, the fire-scorched wall, the exploded tire and other forms of physical eviddence can be powerful allies. They can be mailed when appropriate, or shown to a company representative, but they should not be discarded until all hope is lost.

In 1967, an adjuster for a dubious moving company visited our home to discuss our losses after protracted, three-cornered negotiations involving his company, us and the Interstate Commerce Commission had failed to produce a settlement by mail. We found him unmoved by such items as a box marked "sweaters" which was empty and a globe for a floor lamp which was unaccompanied by the lamp itself. But when we showed him our dining room table, into which his driver had permanently scratched his name and the date by grinding a ballpoint pen through onionskin paper, he finally acknowledged his firm's liability. Resisting the urge to apply furniture polish to the table saved us $200.

These nine rules are neither comprehensive nor fool-proof, but I trust they suggest that asserting one's rights in the marketplace need not be a futile exercise. The rewards of personal consumer advocacy can be handsome, in money and self-esteem, and the only investment required is time.