It’s not a case of “most cases” – it depends very much on the individual apartments and how strictly they enforsce their by-laws (if they even have any related to shades). Older apartments that have over-exposure to sunlight may well have shades already. Newer apartment block may well have more shade built in.
You won’t be able to get prmission in advance, but you could get a good idea of your likelihood of success by contacting the building’s strata committee or strata manager.
As you will be attaching the shade to common property and it will affect the outward appearance of the block even if it is allowed there may be a restriction on the style and colour of the shade. All you can do is ask.