Building a baseball stadium in Washington would cost $342 million to $542 million, depending on which of five sites was ultimately chosen, according to a report that city sports officials sent to Major League Baseball this week.

The 70-page report portrays a prosperous, baseball-hungry city ready to support a team in a 41,000-seat stadium with easy access to Metro and regional highways and views of the U.S. Capitol or Washington Monument.

But it also projects costs that are likely to run $100 million higher than estimated in a 1999 study, and opponents of the project quickly seized on those as evidence that the cash-strapped city cannot afford a new baseball stadium. City officials said the higher estimates, which account for inflation through 2005, resulted from rapidly rising land prices and a rigorous effort by the report's authors to include all expenses.

"It's expensive, there's no question about that," said John L. Richardson, chairman of the D.C. Sports and Entertainment Commission. "But I don't think that will come as a surprise to Major League Baseball."

A consulting team analyzed 32 sites and settled on five, including one in Northeast Washington, just north of Robert F. Kennedy Memorial Stadium. Three of the potential sites are near downtown: east Mount Vernon Square, the new Metro stop under construction at New York Avenue and a site near Union Station, just north of Massachusetts Avenue, that would require the closing of a portion of New Jersey Avenue. A fifth possible location is on the Anacostia River waterfront, adjacent to South Capitol Street.

The sports commission, which paid for the 1999 report as well, developed the new one in conjunction with the office of Mayor Anthony A. Williams (D) and the Washington Baseball Club, one of three ownership groups seeking to bring a team to the area. The cost was $270,000 plus expenses that are still being tabulated; city officials said they had not agreed on how much of the final cost would be paid with government money.

A D.C.-based team of six consulting groups, led by Brailsford & Dunlavey, wrote the report, which considers costs, architecture, sites and other facets of building a stadium. It was to land in various league offices Wednesday. City officials said they had heard nothing back from baseball officials, who also did not return messages from The Washington Post yesterday seeking comment on the report.

The wide range of price estimates for the five sites comes mainly from differing land costs. The RFK site, which would be on land already controlled by the sports commission, would be cheapest at $342 million, but it is also farthest from existing amenities such as restaurants and shops. The Mount Vernon Square site could cost as much as $542 million because surrounding land is expensive.

Clustered in the middle, between $411 million and $436 million, are the three other sites, including New York Avenue, the Anacostia waterfront and the site northwest of Union Station. The 1999 report estimated the cost of a stadium at no more than $330 million.

"You have five viable sites, all with certain strengths and weaknesses, all of them very viable, very acceptable sites," said Frederic V. Malek, head of the Washington Baseball Club. "I think it makes a statement to Major League Baseball that this city is prepared and ready to host a team."

But Robert L. Johnson, head of a rival group bidding for a team, said, "Wow!" upon hearing the new estimates and suggested that the city must consider a far heavier investment of public dollars if it wants a team. Williams has pledged as much as $200 million in public funding for a stadium.

"I think the city has to revisit that number," said Johnson, whose possible ownership group includes Redskins owner Daniel Snyder. "It would be difficult for me to contribute more than $100 million toward any stadium in any kind of public-private partnership."

A third group led by telecommunications executive William Collins III also is bidding for a team that would play in Northern Virginia. He said yesterday that his group, along with state financing, could build a stadium for $300 million, but he has released few details and declined to publicize possible stadium sites in the region.

Last night another group, the Virginia Baseball Stadium Authority, approved a contract with the architect HKS Inc., the Dallas-based firm it chose to design the stadium last month. Gabe Paul Jr., executive director of the authority, said that the $300 million figure was based on 1997 numbers and that HKS will need to update cost estimates and evaluate the sites under consideration.

Opponents of a new stadium in Washington said the city could not find the money to pay for half the cost of a stadium without cutting basic city services, which already are stretched by an ongoing fiscal crunch. Just last month, the D.C. Council reduced its budget for this fiscal year by $323 million.

"You would hear a clamor from people," said D.C. Council member Sharon Ambrose (D-Ward 6). "Let's put $200 million in school infrastructure. Let's put $200 million in affordable housing. In a city that's still as needy as Washington, D.C., is, there are a lot of cries for different needs."

The report lists several possible sources of public money, including stadium taxes, a new sports-themed lottery game and income tax on salaries earned by players throughout the league who would play at the stadium.

It also estimates as much as $10 million in direct annual economic impact and $15 million in indirect impact such as spurring private development near a stadium.

Economists who analyze sports franchises say that publicly funded stadiums rarely if ever generate enough tax revenue to pay for themselves because they mainly redirect entertainment dollars that would have been spent in the community anyway. They say stadiums should be regarded as amenities, such as public parks, that cost money rather than make it.

"It doesn't pay off economically," said Andrew Zimbalist, a Smith College economist who has written extensively on professional sports. "Money that goes to a baseball team tends to go to wealthy players and wealthy owners."