There are quite "affordable" sinks available from sanitary supply stores. Also stylish ones. Some (e.g. ours from Ker..g) are wall-mounted, but can also be used as countertop sinks, then the underside is polished. Nevertheless, there will probably be a cutout in the countertop. I wouldn’t buy a sink at Elch, and I would also avoid plastic, as it can smell after a lot of use. You should have some improvisational skills at Elch, otherwise it won’t work. The advantage is that the same surfaces can be found in every department – so you can equip a nightstand with wheels and use it as a shelf for the tub, or you can take the extractor cabinet and mount it under the ceiling in a row.