In the immediate term, as someone in a high CoL city with an out-of-control rental market I'd really like these tools to be open source. Then at least they're extremely useful in distinguishing you from other applicants, by virtue of being an 'exclusive' tool, in the sense that not everyone has enough technical expertise to deploy the necessary services to run them. It also has the benefit of encouraging collaboration around this ecosystem of tooling (the user pool is after all already restricted to software developers, data scientists, and fairly technical hobbyists)

But then if you open up the hosted version to the public as a paid service (someone probably will, and it's really only fair to offer the same strategic advantage to less technically inclined people; perhaps some of those people need it more) you may end up in a situation where it becomes a requisite in the rental search; you'd be at a significant disadvantage if you don't use it.

I don't really have any concrete conclusion from this train of thought, just that it's a complex situation which can really only be fixed with regulatory oversight, and in the mean time these markets will arise to give people an advantage, that also aren't equal-opportunity due to cost.