Sorry ladies this isn't exactly what curating means. Not to diss an argos or second hand sofa, that is all perfectly fine, but curating it is not! :-)
If you wanted to truly curate a room, I guess, at a push, you would research each piece of furniture, the designer, when and where it was made, you would move through the room with a definite plan of how to best display the design classics of the time in relation to each other, there would be at the very least tentacles of unity between pieces, same age but different countries, same designer but from different eras of their career, the art and 3D pieces, lampshades, door handles and such like would all link to the common idea, hence bringing a sense of completeness and education of a particular design or age to the room and being able to impress, I guess, your guests, or show a passion and hopefully they leave with a deeper understanding of the influence of your chosen pieces on that particular time, reflecting social and commercial developments of that time and place.
Painting a new build's living room walls, buying a sofa and throwing in some pretty cushions is not curating. You might get away with it if you are using modern, designers, acknowledge in their field, reflecting society today with pieces that will stand the test of time, but this is very difficult, as it's not an exact science to know which pieces will come to reflect the 21st 20s.