I wouldn't say it's a bad report and it's generally a lot better than some we see on here. The issues have been found, it's a matter of the severity of them really.
Strictly speaking, to satisfy the findings, the first one is easy, as said above fit a blank.
The C2 - Cable's wouldn't be allowed to be directly buried in walls < 50mm deep without RCD protection today. How to code it in older installs is one of the things that is interpreted differently by different people. The industry best practise guide says it's a C3. A guide produced by the scheme the electrician belongs to says it's a C2. To fix that would involve adding RCD protection to all circuits. And here the fun starts.
I'd say the consumer unit is quite an old one as the breaker sizes are B5 and B30, not B6 and B32 which have been common for a long time. It's interesting there was an (early?) RCBO available for it at all, someone might be able to identify it from that alone. (
@westward10 ?)
I can't imagine being able to easily upgrade that board and add RCD protection as the parts probably won't be sitting on shelves (new), and it will become an eBay scouring job. The same applies to the failed RCBO.
So the consumer unit's age might dictate it's replacement anyway due to lack of parts.
Personally I probably wouldn't have given a C2 for the buried cables, but would have been advising replacement anyway. If thought there was a socket that could potential supply equipment outdoors I might have added a C2 for lack of working RCD protection and we arrive back at the same place.
(I'd also be suggesting a return visit in 6-12 months to measure the external earth loop impendence again as it's right on the limit for the earthing type. (0.37 ohms, limit is 0.35 ohms). If it stays static, fair enough. If it has worsened the supplier need contacting as it's their problem.)
