If you have been notified that your apartment building is being converted to condominium ownership, you face the hard question of whether to fight it, buy a unit or move out.

It's not an easy decision. In many such situations, the tenants are long-time residents who have made good friends in their building and established good contacts in the neighborhood. Finding equivalent rental quarters - at reasonable prices - is becoming very difficult in the District of Columbia, where 1,000 apartments were converted to condominium ownership so far this year.

District landlords are required to pay relocation assistance of $125 per room, not including kitchens and bathrooms, to tenants who are evicted because of substantial rehabilitation or demolition. This assistance may also be available to tenants in a conversion situation, but only under limited circumstances. The law has a complex formula to determine who is eligible; tenants with questions can call the hot line at the city's Rental Accommodations Office, 7245600.

if your building is being converted, the condominium law provides that each tenant must be given at least 120 days notice of the conversion before they can be served with a notice to vacate. The notice of conversion must be given within 10 days after an application for registration of the condominium units has been approved by the District government.

During the first half of the 120-day period, each tenant has the exclusive right to purchase his or her apartment unit. Developers have been offering substantially reduced prices to tenants if they make early commitments to purchase. If you are faced with such an offer, contact the condominium office of the District government to determine whether the notice is in compliance with the city law.

A decision to fight the conversion requires careful evaluation and planning. More often than not, the developer will have competent attorneys who keep the condominum conversion well within, the letter of the law.

This does not mean, however, that tenants whould give up their apartments without a fight. Here are some suggestions for immediate steps to take.

Check to see if the certificate of condominium eligibility is proper. A tenants' representative should look at the application filed by the developer to make sure that the information given the govenment is correct and current. Often a developer will furnish the District out-of-date information, and this may be grounds for a challenge.

A petition can be filed with the Neighborhood Improvement Administration asking to have the certificate of eligibility for conversion revoked - if the developer's application is based on improper or erroneous information. The administration is located in Room 900, 1341 G St. NW.

If there are housing code violations in the building, the tenants' organization should contact the D.C. Housing Department and arrange for a comprehensive inspection of the building. Report violations to the Neighborhood Improvement Administration; there may be grounds for revocation or suspension of the conversion plans.

In every apartment complex, there will likely be four divergent tenant attitudes. One group will take the position that they should fight the developer - all the way to the courts if necessary.

A second contingent will decide that it is time to buy condominium or cooperative units, and may not want the strength of a tenants' organization to assist them in getting the best deal from the developer. This group may decide to purchase the building themselves and do their own conversion.

A third group of tenants will decide to move out and may need assistance from the Districe government, including relocation funds or additional time in which to find suitable lodging.

Still others will be apathetic, uninterested in the tenants' organization and unwilling to contribute to a legal defense fund.

Tenants may find that they have to establish two organizations within the same apartment complex. The first is a tenants' group concerned with fihting the conversion and obtaining relocation assistance. The second can best be descrived as an "ad hoc purchasers' group" concerned with the actual development of the condominium or the cooperative.