Is an extra circuit / residual current device really necessary for the office?

Okay, if I understand correctly, then the extra circuit and RCD would also ensure that if, for example, something else in the rest of the house trips the RCD, my PCs stay on, right? If I only have one fuse (MCB) for the room, despite the extra circuit, then the office is off when the RCD trips?

We are currently leaning towards just having it done. Let the sparky earn his 300€, better we have it installed and end up not needing it than not having it and later thinking "we should have done it."

But he can shove the offer with the 600€ patch panel & switch.

that if, for example, something in the rest of the house trips the RCD, my PCs stay on, right?

Exactly. Just the extra circuit with the circuit breaker is not sufficient. That would also become powerless if the RCD in front of it, to which the rest of the house is also connected, trips. In case of a fault, for example, on a kitchen appliance.

With a separate RCD and circuit breaker, even in one enclosure if you want. Your PCs stay on.

For that reason, I, for example, did not hesitate at all and equipped the house with significantly more RCDs etc. than necessary. Or rather, I find the one and now two RCDs mandatory far too few. But that is just my opinion.

We are currently leaning towards just having it done. Let the sparky earn his 300€, better to have it installed and not need it in the end than not have it installed and later think 'we should have done that.'

Very healthy mindset.

But he can shove the offer with the 600€ patch panel & switch.

Same here. Especially network cabling and patch panels and also the rest — a software developer should be able to manage that in no time.

We finally signed the amendment offer yesterday. With a bit of gritting our teeth, but we left almost everything in. After sleeping on the resentment for a few nights, we then decided that we should think about ourselves. If we remove things just because we don’t like the electrical company, then we are the ones who will be annoyed in 5 years when something is missing. You just have to differentiate and sometimes also give money to someone you actually don’t want to. At least the general contractor has been accommodating/problem-free. The second FI, which is now mandatory, was accepted without any issues, and the larger distribution (which partly comes from contract components and partly from our own additional installations) is fully covered by the general contractor. We also added a cable duct for the TV. Also here: sure, the electrician we’re not enthusiastic about will make more turnover, but: do I want to rip open the wall myself later? No. Now he wants an extra €100 to install the CAT cables (according to regulations) in conduit. Actually an outrage, but I’m tired of the discussion, fine by me, as long as they go into the conduit.

I would have handled it similarly since your concerns were not unfounded: Therefore, involve GU in the responsibility and have them share the costs. Ultimately, for all three parties, it’s not a big deal in the end and another point checked off.

It just shouldn’t become the rule.

Just by the way:

An RCD for protecting PCs is totally nonsense from an IT perspective. The RCD is there to protect people, not devices - and that's exactly what it does. If you want to properly protect your PC and your data is important to you, even if the RCD trips, there is a power outage, or something else happens, then you get a €150 UPS for the office. That covers all bases and you don't have to worry about anything.