When the dust settles at Monroe House at 522 21st St. NW and the last apartment has been sold, tenants say they're going to write a book -- "Strange Encounters of a Condominium Kind."

If even half the encounters in trying to convert the 112-unit building -- where 85 tenants have bought their own apartments since sales began in September -- are put down on paper, a best seller in Washington's real estate, legal and financial circles might emerge.

An interesting chapter could be written, for instance, about the four residents who always paid their rent but whom no one had ever seen. The tenants, listed as Pierre Poelman, Joseph Crispin, George Lasrado and a "Monsieur Ducr'e," put down substantial deposits through a friend to buy condo units at the discount price for tenants.

But they never showed up to sign their sales contracts, and couldn't be located in the various European cities where they seemed to be perpetually on business.

In fact, the four never existed. They were the fabrications of a would-be investor -- the friend, who also paid their rents and lived in the building, and who wanted to buy more than his share of the Monroe House units at the discount prices.

Residents contend that their dealings with Washington law firms and lending institutions would also make interesting reading. Several lawyers active in real estate, for example, would only provide counsel to the tenants in exchange for lucrative percentages of Monroe House's gross sales -- a fee arrangement considered musical in condo conversions.

Had the tenants gone along with any one of the four propositions made to them by city law firms, they could have been charged more than $150,000 for aid in converting the building -- three times the legal bill they ultimately paid.

The tenants say there were also demands by prospective appraisal firms for under-the-table "finders' fees" -- in addition to the charges for regular work. The tenants talk about the multitudes of local and out-of-town investors who had schemes to solve all the tenants' problems -- in exchange for a 25 percent to 40 percent equity interest in the building.

The cast of characters was also said to include realty professionals with homes elsewhere who, once they heard the building was going condo, would innocently arrive at the scene to "rent" and occupy units.

On top of this, squabbles and intrigues arose among Monroe House residents themselves as they struggled through their metamorphosis from rent-controlled tenants to prospective real estate developers and owners.

"You'd be amazed at what we've seen and done for the past nine months," said Sarah Maddox, head of the tenants' association, "-- all because we decided to convert our building ourselves, rather than hire any outside developer. If this was a slice of the real estate business in D.C., God, am I glad I work for the State Department. I couldn't take all that slippery stuff that goes on."

The most recent saga of Monroe House, a 1960s-style high-rise, began a year ago, when the Oliver T. Carr Co. announced its intention to sell the Foggy Bottom building. Under District law, tenant associations have the right to make a counter proposal to purchase their buildings; the Monroe residents decided to organize and buy.

Unlike the dozens of other tenant groups in the city who have gone the condominium conversion route, Monroe House's tenants decided to do it completely on their own.

"It was a fundamental decision-point for us," Maddox recalled. "We knew that the usual way to 'go condo' was for the tenants to strike a deal with a developer. The developer would handle all the rehabilitation, design and upgrading, and the tenants who purchased units would get prices discounted below the market value.

"We talked to a lot of other tenant groups who had converted with developers' help," she said. "I guess it struck us that we could -- if we really put time and effort into it -- act as the developer ourselves, own and control the building, control the quality of the rehab better and even come out financially much better, all on our own."

None of the more than 100 residents of Monroe House had any experience in real estate. Only one had even owned a home. Most of the people in the association are middle-income and single, and work in nearby federal agencies and business.

A handful of the tenants are retired, and several are in their 80s. A few have law degrees, one is a university statistician and several have formal training in economics-related fields and work at the World Bank or the International Monetary Fund. Maddox, who has a master's degree in business administration, is a management analyst at State.

All the tenants had lived in Monroe House under rent controls, and as a result, their monthly rents had been depressed for years. Rents this year ranged from the low $200s to the low $300s: They knew that conversion to condominium ownership would double or triple their monthly costs.

But once they decided to buy and convert on their own, the tenants quickly organized into committees that interviewed representatives of 16 brokerages, six law firms and eight engineering companies, as well as appraisers, contractors and prospective lenders.

The tenants negotiated a $3.95 million contract with the Carr company -- $450,000 below the asking price -- and raised $220,000 among themselves for the deposit. They then began the search for a lender who would finance the purchase and an estimated $1.7 million in renovations the building needed.

They also hired someone whom they now describe as their most important adviser: Joanne Pernik of Begg Inc., a real estate firm. Pernik landed the contract for her company to handle individual unit sales in Monroe House at a cut-rate commission -- 4 percent per unit.

But she "went far beyond the call of duty in helping us through the maze of real estate customs and traps, and holding our hands through an incredible number of meetings at night," Maddox said. "Without her, we would have fallen on our face a lot more than we did."

As it turned out, there were plenty of opportunities for the tenant association leaders not only to fall on their faces but to cut themselves in for bigger shares of the conversion profits.

"Once people began to understand that we actually might be able to buy this building and sell it off in pieces," said one member of the tenant board who requested anonymity, "you should have seen the pure capitalism start spilling all over the place.

"I mean, people who were the quietest, nicest tenants you'd ever want to meet in the hallway suddenly started reading The Post's real estate section for the first time in their lives, and began seeing Monroe House as some sort of gold mine. They began counting the tens of thousands of dollars they figured they'd walk away with in profits, and then started wanting even more."

A few tenants' desires for big profits precipitated several of the toughest in-house fights during the nine-month conversion period. Some tenants wanted to buy and rent out several units -- at the $85-per-square-foot tanants' discount price instead of the $105-per-square-foot nonresident price. The majority of the association voted against multiple sales, though, to preserve the owner-occupant character of the building.

Some tenants also wanted to take a Darwinistic line on the affordability issue: If you can't afford to buy your own unit as a condominum, then you've got to pack up and go. That would have meant that a number of long-time elderly and handicapped tenants with low incomes would have to be evicted and their units put into the pool for profitable sale at outsiders' prices.

The Monroe House board ultimately solved the issue by selling units occupied by elderly or infirm residents to investors who agreed to guarantee life tenancies to the elderly at 1980 rent levels.

The investors got the in-house price, averaging $33,000 to $50,000 per apartment, and favorable financing. But they also got an investment with a built-in negative cash flow: The rents cover only about a third of the monthly costs of the mortgage and condo fees.