I have a couple of comments to some posts that have been made, sorry I haven't copied down who made them:
PRE no longer is necessary. Cubans do not need an exit visa to leave Cuba. The requirement is that they must return once every two years. If they are going to be out of Cuba more than two years then they can apply for the PRE and this must be done in a Cuban Embassy/Consulate outside of the Country ie in Canada etc., or they apply to have their passports habilitated.
Regarding the comment about the legalization (ie MINREX stamp) on Cuban documents ie police, birth, marriage certificates etc., the MINREX stamp is a complete cuban process and its a complete money grab. As of April 2014 Cuba changed the cost and process for obtaining these documenets and now its difficult to get them without payign the extra in CUC to have this stamp on it. Its not impossible thought. In theory, the Canadian Embassy has never required a MINREX stamp etc. Cuba will tell you that it is required for that document to be used outside of the COuntry. Canada doensn't need it and in most instances if you bringa document to Canada to use under other purposes most people have no idea what the stamp is. However, the one thing to remember is that the Canadian Embassy is manned by local engaged staff and often what happens, especially on files where people are not represented ie by a lawyer/immigration consultant is that they will tell the individiucal that it is required. You may or may not get lucky and not be asked to get it.