Senior officials at the Department of Housing and Urban Development took two dozen trips last year to places ranging from Martha's Vineyard to Milan, Italy, in which their air fare or hotel costs were paid by groups of real estate agents, builders and city and county officials.

HUD Undersecretary Donald I. Hovde, for example, spent two days in Puerto Rico in September as a guest of the Pennsylvania Association of Realtors, according to department records. The group paid for his stay at the Cerromar Beach Hotel, where single rooms start at $105 a night. Hovde also took a six-day, $3,600 trip to Italy, where his plane fare, hotel and some meals were paid for by the Italian chapter of the International Real Estate Federation.

Builders, realtors and cities and counties all receive money from HUD and are affected by a variety of department decisions. The travel financed by these groups is in addition to numerous trips to London, Paris, Athens, Geneva and elsewhere that senior department officials took last year at government expense.

HUD policy prohibits employes from accepting free trips from specific companies that are regulated by or do business with the department. But, in a memo last May that largely continued what had been Carter administration policy, Hovde encouraged senior employes to accept free travel from trade associations, "regardless of whether the industry or group is regulated by HUD or the members of the association have business dealings with the department."

"Current fiscal realities make it appropriate that such offers be not only accepted but encouraged," Hovde wrote, "even to the extent that the organization's willingness to reimburse expenses will be taken into account in the department's determination of whether to approve the travel."

Hovde added, however, that free travel should be discouraged in some circumstances because it "may tend to create a public impression that the offer is made to influence the department's official actions or to obtain preferential treatment."

Asked this week about his own travel, Hovde said his eight expense-paid trips were "just part of the invitation. I've checked with the general counsel's office and it's perfectly legitimate."

Hovde said he went to Milan for a conference of Italian officials and real estate executives. He said he met with a number of housing and municipal officials on his six-day trip to the Virgin Islands and Puerto Rico, where he said HUD provides substantial housing aid.

"I was just busy, busy, busy while I was in San Juan," he said. "I have no reservations about that in any way, shape or form."

Michael Bernardo, an official with the Pennsylvania realtors, said Hovde was invited to their convention because he is a former president of the National Association of Realtors, and "We thought it would be a good idea to have him tell us what's going on in Washington. He was on the program. We don't bring them in to have fun."

Hovde spoke to 19 realtors' groups last year. The Colorado Association of Realtors paid his hotel bill in Denver, while the National Association of Home Builders paid for part of his trip to its Las Vegas convention. When Time Inc. staged a housing conference in Williamsburg, Va., the company paid for Hovde's hotel and flew him there in a helicopter.

Stephen Bollinger, HUD's assistant secretary for community planning and development, had some expenses paid on 10 trips last year. On an August trip to Orlando, the Florida Association of Housing and Redevelopment Officials paid for his stay at the Hyatt Regency Hotel. An affiliate of the redevelopment group paid his hotel bill in Sioux Falls, S.D., and the New Jersey State League of Municipalities paid for a two-day stay in Atlantic City.

Bollinger said that he had just turned down a free trip from a mortgage banking firm because it would look improper, but that he could do nothing for trade associations.

"The Florida association would never have any business before me," Bollinger said. "There's no way I can exercise any discretion in funding them, even with their willingness to pay for my hotel.

"The test I have is, are these guys pimping me? Am I being brought there to be manipulated?" He added that such trips "provide an opportunity to communicate the kind of information they need . . . and not have the expense borne by the taxpayers."

Bollinger said his $3,900 trip in September to Britain, Switzerland and Bulgaria was for a conference on development and was partially financed by the State Department.

Federal Housing Commissioner Philip Abrams accepted expenses for three trips last year. Associated Builders and Contractors paid Abrams' hotel bill at its Las Vegas convention, the Phil Donahue Show brought him to Chicago for a television appearance and the National Housing Rehabilitation Association paid his air fare and a night's lodging in August at Martha's Vineyard.

"I have limited travel funds," Abrams said. "This allows us to communicate with people in the private sector about changes in housing programs, and to cut down on misinformation."

HUD Assistant Secretary Emanuel S. Savas took a trip to New York that was paid for by the American Jewish Congress, and two trips to London partially financed by British authorities. The Reason Foundation, a libertarian think tank, paid Savas' expenses to address the group in Santa Barbara, Calif., and gave him a $250 honorarium.

HUD rules prohibit accepting fees for discussing department business. Savas said he took a half-day's leave to address the group on his recent book, "Privatizing the Public Sector." But foundation president Bob Poole said Savas also spoke "on what HUD is doing and some of the research in his division."

The Washington Post reported yesterday that Savas, a strong advocate of cutting federal aid to the cities, charged the government for more than $14,000 in travel last year, including five trips to Europe and 20 trips to New York, where he spent weekends with his family in Tenafly, N.J., after conducting official business.

Savas said these were all legitimate business trips and that he saved money by avoiding hotel costs in New York. A White House spokesman said yesterday that presidential counsel Fred Fielding has no plans to look into Savas' travel.

Two months ago, Hovde agreed to repay the government $2,800 in overtime costs for using a HUD car to commute from his home in McLean.