I like the idea. „Hey I have a life treating condition and it might help if x is filtered out in my kidney, is that possible? Of course that will make an additional 5€/month , but since we would loose one of our valued customers we will give you 30% of for the first six months“

Somebody know some bio engineers, I’m hiring.

This is the basis of the book "The Repossession Mambo" [0] and the (slightly less good) film "Repo Men" [1].

They're about what happens when you can no longer pay for your artificial body parts (the repo man comes and reclaims their property).

0: https://www.goodreads.com/book/show/6283942-the-repossession...

1: https://en.m.wikipedia.org/wiki/Repo_Men

Also, the plot of the wonderful 2008 rock opera, “Repo! The Genetic Opera”.

https://en.wikipedia.org/wiki/Repo!_The_Genetic_Opera

Dialysis is kidney as a service.