Here are some general ideas.
In almost every single point below there are exceptions but it is a good general guide.

Advantages of Hotels:
More possibility of leaving stuff somewhere if you arrive early or leave late.
Most hotels have an almost unlimited supply of hot water.
If you have a husband who makes you do all the cooking you can have a rest because you will have to eat out for every meal, so no washing up, cooking or cleaning.

Disadvantages of Hotels:
Much more expensive for groups of more than 2.
No possibilty of preparing food.
When booking it is rare to be able to choose the exact room.
Hotels normally have professionally taken pictures of the best rooms which probably isn't the room that you actually get.

The place to book hotels is here:
https://granadaforo.granadainfo.com/hotel-aggregators/

Advantages of apartments:
Much cheaper for groups of more than 2.
Better value for money because there is normally a kitchen and lounge.
More square metres per unit.
Much wider choice of location in Granada.
Possibility of using kitchen to prepare locally bought food or for special diets.
Apartment websites normally give better information and better arrival instructions.
It is more common to be able to see in advance exactly which apartment you are going to stay in.

Most apartments have a washing machine to do laundry

Gives a more realistic idea of how people really live.

Disadvantages of apartments:
Apartments often don't have an unlimited supply of hot water.
The arrival may be more demanding because there is not a 24 hour reception although nowadays many apartments have smart locks.
There is normally no room service.

To book apartments use airbnb 

Also sites like booking.com also have apartments

https://granadaforo.granadainfo.com/hotel-aggregators/