DIY washbasins, what accessories do we need?

Just threw in our solution completely out of context. Old dresser (eBay Classifieds €20) + sink €60, granite slab from the stonemason roundabout €200 including cutout, made according to sink dimensions (used as cutting template). Everything else is standard measurements regarding the pipes. Up to the hole in the wall/floor, it’s like Lego. Just connect the right parts until the water flows where it’s supposed to. In our case, a flat siphon was the best solution.

Wow, how cool does that look :O I’m also already considering whether I could come around to something that stands on the floor again. But it can’t be that I don’t get my desired washbasin because I can’t find anyone to hang it on the wall for me. If worst comes to worst, I’ll just try it myself, there are YT tutorials after all and you can replace tiles if you have the necessary money. Maybe I’m just too scared.

Buy the right drill bits and have it explained to you on site. Drill a small pilot hole first, slowly, without impact, then drill larger afterwards. It will work..... as long as you don't use force or drill into a cable, nothing will happen. They will explain that to you at the hardware store as well, so you use the right materials.

Today our washbasin countertop finally arrived.
We want to install a 30cm deep cabinet from Ikea in dark brown underneath (it's all for the guest WC).
I will order a suitable faucet, a non-lockable drain (if not included with the faucet), and a siphon from Reuters.
I think that should do it.
I have a Bosch rotary hammer, and I would buy a 35mm and 45mm hole saw for that (or what are these parts called for cutting holes?), in case I don't find anyone to install and also saw them for me (I would prefer if a professional does it).

Did I forget anything?

I can completely understand you. We have the same problem. Didn't find any suitable base cabinets and thought we’d just put something underneath ourselves or buy some nice ones somewhere. The problem now is that the 2 washbasins, because of their width and how far apart they are, are not standard. So for example, if we took 2 base cabinets at 80 cm each, it wouldn’t fit at the back with the cutout on the base cabinet for the siphon. And you also don’t want a 2 cm gap between the two base cabinets. And a large continuous cabinet under 2 washbasins doesn’t work either because the cutout for the siphon is already fixed and then doesn’t fit with the washbasin width. So we went to the carpenter and got several quotes. The cheapest was 2,600.... for a base cabinet about 170 cm wide and 2 drawers... for that I could have also had a very nice one installed through the general contractor. We actually regret that now. And we still don’t have a cabinet :-/ How is it with the Ikea cabinets? There is already a cutout for the siphon in the center of the cabinet, right? If it’s completely open at the back, maybe you could actually make something nice from that.

Which Ikea cabinet do you want to put underneath? Or hang? Wouldn't it be nicer if this board hung freely on the wall? There are these brackets where you can also hang a towel on each hanger. Or you could have something made from steel runners and place it, which is really cheap and versatile to buy. If the Ikea cabinet is narrower than the board, then these are usually open at the top as far as I know. Basically, you can also hang kitchen wall cabinets from Ikea under the board or one/two Metod drawer cabinets or the Godmorgen.... in gray and wide it is very stylish. With this beautiful basin, you must ask exactly which drain fits or ask the manufacturer.

The basin and the plate look good. Keep at it, it’s not run-of-the-mill, but you’ll manage it!