In The Expanse, a painted Ikea "washcloth hanger" that looks like an octopus is actually a game for special childrens. Also a 3d connexion space mouse is used to control the rocci. I kind of hate spotting them tho.
The Expanse used a ton of off-the-shelf props; most of them were used cleverly enough that they didn't stand out too badly. My personal favorite was a couple of laptop coolers used as "vents" in a maintenance passage: https://i.redd.it/rn2iac41t8h51.jpg
One of the real skills of commercial model and prop making is know all the corners you can cut, and things you can reuse.
To take an example from Aliens, the ship is only seen from one side, so the model only has one finished painted side, and the interior sets scavenge loads of bits and pieces from computer cases and whatever.
You also shouldn’t underestimate the tradition of hiding Easter eggs in models and sets.
> Also a 3d connexion space mouse is used to control the rocci.
Did you know that the SpaceMouse got developed by the German Aerospace Center (Deutsches Zentrum für Luft- und Raumfahrt) as DLR SpaceMouse for controlling robot arms in space?