You mean like physical in game that can be reacquired through more nefarious ways or more like what @Vavrik mentioned? Honestly I am not sure they have really thought out the full market system for the game yet.
Just be careful of check valves as they do a great job of preventing back flow they also create a situation where upstairs flushing leads to downstairs overflowing.
Since it was featured on https://robertsspaceindustries.com/community the amount of noise and dirty data has skyrocketed to the point its not very helpful anymore.