Installing new plates for powerpoints?

I have been looking at some nice new cover plates for the power points in my newly purchased apartment (built in 1979), but am unsure how exactly these would be installed.

I want some with USB outlets and most with 2-4 outlets, but is it that easy? Does the electrician have to do anything to the in-wall wiring and then put on the relevant plate?

Also, how difficult do you think it might be for extra power points to be installed in a level 1 apartment (there are 31 levels in total, we're the first one off the ground) on both internal and external cement / brick walls?

Thank you!

If they are just cover plates, and fit your existing power points, then you can just clip off the existing ones, and clip on the new ones yourself. However it would be very unlikely that there are cover plates available now that fit any switch made in 1979.

More likely what you are looking at is replacing the power points. This would be a simple job for an electrician, assuming the old and new ones are standard size. Extra power points is a lot more work, as the cabling has to be chased through.

Thank you!

So...if a new power point was installed, and say the old one had 1 outlet and the new one had say 2 outlets and 2 USB outlets, would that work? Or would the electrician have to do something inside the wall with the cabling?

The wiring is the same for all of them. The ones with USB sockets may be a bit deeper in, so may need some more clearance in the hole in the wall, but apart from that are basically drop-in replacements.