Sanitary offer - realistic & reasonable?

Are the pipes basically all standardized (diameter and distances for cold and hot water) so that you can install them without objects, and then mount the fittings yourself?
Or do you at least have to know in advance what you want to use in order to make the appropriate specifications?

It should be standardized.

Honestly? Get annoyed, grit your teeth and sign, and receive a warranty. Our rain shower from Grohe including the faucet cost almost €1400. That's just how it is - the plumbing company, the general contractor, and the retailer all earn money on this, including installation and warranty for the installation. They just charge a premium for that.

We have the Concept 300 here in both showers. It was the "house brand" at the sanitary wholesale of GU-Sanis. Although that is the only thing we took from the brand, they are great. It wasn't (and still isn't) completely clear to me what others could do better. A lot of water comes from above on the 30x30cm. At least my wife hardly ever uses our additional hand shower, if that is a quality feature.

I don't want to do it myself. With such a high amount, however, it is worth checking whether it is worthwhile to remove the work from the contract (and thereby lose benefits such as warranty, etc.).

You won't get a plumber to come for that. Forget it.

I recently asked my plumber the same question, what the difference is between the cheap self-installed ones and the expensive ones from a professional.

- Labor time (installation can easily take 2 hours, depending on complexity (mine came almost in individual parts)
- Risk of installation damage must be factored in (tiles breaking, etc.)
- Warranty
- Spare parts available even after years
- Margin (yes, he also has to make some profit ;) )
- Metal and glass instead of plastic (also inside)
- Polished parts for less water noise and smoother sliding control elements

With my Hansgrohe, I actually can't feel any plastic parts. Maybe there's something to it, maybe it's just the margin. At least that's how it was explained to me.

Working time (assembly can easily take 2 hours

I was, for example, surprised that the base cabinets were delivered fully assembled. Not like at hardware stores in individual parts.

Thus, you have a high-quality factory assembly. Which is then, of course, factored into the material cost.