I can confirm the delivery in cardboard boxes (without water). It contains the individual parts and illustrated instructions.
The assembly is easily done with average Ikea furniture knowledge (Billy level recommended, Pax level not mandatory). I would estimate the effort at 30-60 minutes.

When it comes to the process: it is delivered with Post Logistik, i.e. you get an email/SMS beforehand to notify you, where you can choose a time slot. The two parcels are then delivered from the van to your door. The two parcels are bulky and not very light, but they are reasonably manageable, so that you can manoeuvre the rest into the house/flat (especially if there are two of you, no problem).

Delivered in several cardboard boxes. The central unit around the drum is pre-assembled. Without water 🤪.

Two packages come. A large box with the fully assembled drum incl. pulling mechanism and the screws, etc.. A second long and narrow package contains the runners. Assembly is relatively easy, you just have to screw it together. My problem was that only the runners were delivered, but not the large package (in the first lockdown chaos in the warehouse, two loose packages, etc.). But the quality is TOP. I've seen other fluid rower that didn't convince me....