Rental Complex converted to Condo but only some were sold and 3/4 remain rentals. Can management force owners to convert to rentals?

Dear Anonymous, Unfortunately without looking at the Declaration of Condominium for your complex it is next to impossible to answer your question.  Generally, the Condominium Association Board could file a lawsuit against you to enforce the Declaration of Condominium.   The Association would need to purchase your condominium from you in order to make the rental their unit to manage or you would need to enter into an agreement with them to manage the unit.