The company that turned the Van Ness North apartments on Connecticut Ave. N.W. into co-operatives has signed a contract to buy the two remaining rental buildings in the complex for $60 million and plans to convert them to co-operative ownership.

Tenants in the 1,058 apartments in the Van Ness East and Van Ness South buildings have been notified of the plans, which would make the project one of the biggest co-ops in the District of Columbia.

Situated between Connecticut Ave., N.W. and Rock Creek Park, at Van Ness street, the complex is now owned by Van Ness Properties Limited Partnership, a group headed by Howard Polinger.

Last spring the Polinger group sold the 466-unit Van Ness North building to Investment Group Development Corp., headed by real estate magnate Conrad Cafritz.

The Cafritz group in turn put the individual apartments in the building on the market at prices running as high as $130,000.

Now the Cafritz group has agreed to purchase the other two buildings and is offering $40 million for the 625 units in the twin towers of Van Ness South and $20 million for the 433 smaller units in the older Van Ness East building.

Because the Van Ness complex is considered a luxury development, it apparently is exempt from a District of Columbia moratorium on converting rental properties to co-operatives or condominiums.

The District's rent control law requires that tenants in a complex be offered a chance to match any offer to buy their project. Van Ness tenants were notified of the Cafritz offer last week.

Residents of Van Ness North tried unsuccessfully to purchase their project, said Betty Shapiro, head of a tenant organization there.

The group, however, succeeded in winning major concessions from the developer, Shapiro said. Tenants were originally offered the chance to purchase their apartments for 10 percent less than the price charged the public. After the tenants threatened to tie up the project in legal battles, their discount was raised to 18 percent.

Later the developers raised the prices to the public, so tenants wound up getting their units for nearly 50 percent less than the public price. About 75 percent of the Van Ness North tenants purchased their apartments.