Another quality electrical installation ? Or an electricians horror story!

Today we had a job to install two mains and battery operated smoke alarms and one heat alarm in a flat that is being renovated to be let out. The job in the whole was easy enough. A 1mm cable from the newly installed consumer unit to the first smoke alarm and then a 3 core linking them all together, A straight forward job and not anything interesting to talk about with our installation and commissioning of the detectors.
But for what every reason the customer had already had the flat rewired by his own electrician and said that his electrician does not install smoke detectors, Hence we got the job. As another electrician had done the rewire I did not feel it was right for me to get involved in what I saw in the consumer unit, All I did was inform the customer that the other electrician should return to tidy up the consumer unit. I don’t know if you can see clearly in the picture I took? But not only was the installation of the consumer unit messy internally as well as externally, But he also had a 32amp mcb on a radial circuit and what seemed another radial circuit i.e. a 2.5mm twin and earth in with a 1.5mm cable in a 6amp mcb! I really thought by now that these types of mistakes were for amateurs NOT competent persons! Another thing that really does annoy me is that this is a brand new install and new consumer unit and the electrician had used another brand of mcb