It all sounds reasonable to me.
If you think it's unreasonable, get another price.

Bigger cables can be a total PITA to connect, particularly in residential installs where everything is so small.
I can see it taking an hour or more if it doesn't go well

I suspect the electrician isn't going to install a plugin MCB. More likely a real MCB in a surface mount box.
Depending on the situation, 1.5 hours doesn't sound unreasonable.

Then there's testing and paperwork, time spent traveling and getting the parts, etc.


Replacing a socket is not the same as replacing a high current isolator.
If you screw it up:
-There is a high chance you destroy the switch.
-There is a medium chance you also destroy the in wall wiring connected to the switch and have to get it replaced.
-There is a small chance that the destroyed wall wiring also significantly damages other wiring and that needs replacing too.
-There is a very slight chance that you burn your house down.

Note that rewiring 2 story homes often requires the removal of wall linings.