Overwhelmed by military conscription - Alternatives?

I am surprised that the installer gave you prices without installation and assembly. Normally, the labor is already priced in and the items are offset against each other. And of course, it’s about the warranty of the installation: in case of any water damage, you won’t find anyone responsible because it is more likely that the specialist did not make a mistake than the layperson.

I am surprised that the installer gave you prices without installation and assembly. Normally, the labor is already included in the price and the objects are offset. And of course, it’s about the warranty of the installation: in case of any water damage, you won’t find anyone responsible anymore, since it is more likely to be ruled out that the professional made a mistake than the layperson.

Now seriously, what could possibly go wrong with installing a washbasin if the angle valves and drain are already in place?

If you really do it yourselves, you have to make sure that everything fits together in the end. You absolutely must give the installer the exact measurements of the drains and the data sheets of your sanitary objects. Otherwise, during the shell construction, they might set everything up as they do for standard items, and then you will have to figure out how to connect the drains and fittings afterward. (WC, urinal, washbasin, etc.) You also have to consider the heights and inform the plumber.

Have you also looked at the internet prices including the accessories? For example, concealed components for the fittings, flush tanks, pipes, siphons, seals, etc.? You could also buy only the washbasin without the base cabinet, which might be cheaper. I would definitely talk to the installer beforehand and ask him where this extreme price difference comes from. It is clear that the companies on-site are more expensive than the internet because they have more overhead costs, but if it is extremely expensive, then it is strange.

Our sink with cabinet underneath was hung up by the furniture store installers. I did the faucet, siphon, and silicone joint myself. Overall, it was by far cheaper than going to the plumber.

Now seriously, what can really go wrong when installing a washbasin if the angle valves and drain are there?

Who is talking about the washbasin?

Now seriously, what can you really do wrong when installing a washbasin if the corner valves and drain are already in place?

Here they talk about shower head, bathtub, toilet, etc. So I don't want to screw on goods worth 15k (want to)

I did the vanity unit with a buddy who does interior finishing. That was a "throw-up job." It took us 4 hours for the heavy piece, wasted countless diamond drill bits so the tiles wouldn't crack.

Never ever...