When a condominium association has a right of first refusal in their declarations what does that mean?

It depends on what the association has '...a right of first refusal' over.

Legally, the right of first refusal is a contracted right that gives the holder -- association in this case -- the option to enter into a business transaction with the owner -- probably of real property in this case -- according to a unique set of terms, before the owner can enter into a transaction with a third party.

If the association has the right of first refusal over the purchase of a unit, then, in order to sell the unit to a buyer other than the association, a seller must first offer the unit for sale to the association, and the association must refuse to purchase the unit.

Once the transaction has been refused, the owner can sell the unit to a buyer other than the association.

The terms of the right of first refusal can include a price, a payment plan and so forth.