Is it correct that it takes only 25% of owners to vote out the present management. If so, what does the 25% consist of? Number of units in building or number of owners?

It depends on your particular condo rules....

My primary condo rules state:

a. To convene any meeting, we need unit-owners holding at least 1/3rd of all votes to show up at the meeting (a required quorum) AND

b. To appoint or dismiss the Manager (which is an extraordinary resolution), we need affirmative votes of more than one-half of the total votes of all unit-owners (attending or not)

(in our case, a "vote" means the number of votes equal to the ratio of Co-ownership in the Common Property of the condo building).

The law states that 50% of all the owners (by area owned) must vote for a new manager.

But if the meeting fails to get the 50% then a new meeting can be called within - is it 15 days??? - then only a simple majority is needed provided the meeting has a quorum of either 30% or one third of owners present or represented.

Sorry I always forget the exact numbers!