The practices of cemetery operators in the Washington area make it "almost impossible (for consumers) to shop around and compare price presentations," according to a report released yesterday.

The report, by the consumer affairs committee of the local branch of the Americans for Democratic Action, found that there is wide range in prices for grave sites locally - from $150 to $2,500 - but that often additional undisclosed costs can raise the price of a funeral considerably.

"We found as the most educated consumers difficulty in understanding . . . there were buried costs and difficulties in digging out information (about pricing information)," Ann Brown. chairman of the consumer affairs committee, said at a news conference yesterday.

The extra costs for such services as grave digging, grave markers and future care of the site could add substantially to the original expense expected by the people purchasing a grave site, the report said. Generally, the report said, burial costs could account for half of all funeral expenses.

The survey covered 20 of the area's 31 cemeteries. There was a wide range of expenses for ground burial, mausoleum crypts and burial of cremated remains among the cemeteries.

In compiling the information, researchers who posed as possible customers found that many of the cemetery operators had no prepared price lists for all services and would offer written lists on the spot only with "great reluctance," the report said.

"Sales presentations are calculated to be confusing," the report said.

An official of a local cemetery operators' association said that most cemeteries distribute some price information. He said, however, that not all such information is given out in printed form.

"We try to give any family full information about what they are going to run into," said Norman Marlowe, a vice president of the Maryland Free State Cemetery Association.

Potential customers are given the costs of the burial services but not of grave site costs. Marlowe said because it might not be used for proper purposes . . . such as sensational stories about the disparity in prices." Marlowe is also president of the Parklawn Cemetery near Rockville.

Committee members assembled the price information by visiting the cemeteries and posing as customers interested in purchasing a burial site for future use.

Twenty-one questionnaires the committee sent out months earlier to the cemeteries were unanswered, while five wrote back declining to divulge their costs. Five others completed the form.

Mount Olivet Cemetery, in Northest, had the lowest overal grave site prices ranging from $175 to $275. Prices at Carver memorial, in Laurel, started lower, at $150, but went up to $330, according to the report.

Oak Hill, a Georgetown cemtery founded in 1849, had the most expensive grave plots at $2,500 for one. "We're filled and a lot of people would give their right arm to get in here," said George Kockley, the cemtery's superintendent.

The highest prices in Maryland - ranging from $525 to $725 - were found at the George Washington Cemetery in Hyattsville.

Cemetery operators said prices varied for grave site real estate as for any other type of real estate because of location and real estate taxes. Church-owned cemeteries pay no taxes.

In addition, some cemeteries offer customers an interest-free installment plan for purchasing lots while others charge from 7.2 percent to 9.5 percent in interest.

The costs of digging a grave and then covering it, costs of different types of grave liners, the gravestone and an insullation fee for markers purchased from anyone other than the cemetery itself are usually not included in the price of the grave site, the report said.

A family can build its own family mausoleum at Rock Creek Cemetery in Northwest Washington for $30.000 or buy a crypt, which one cemetery operater compared to a condominium, for $995 and more.

The cheapest burial prices were for urns containing cremated ashes. These costs can range from $25 with no service at the Harmony Cemetery in Landover to $225 at Gate of Heaven and St. John's in Montgomery County.

Brown and Becky Cohen, who wrote the report, urged consumers to "think about funeral and cemetery arrangements ahead of time when everyone is calm and unemotional" to avoid "being swept into arrangements they neither want nor can afford.