through often not on paper, but in practice, like the people which can throw rocks in your path do that less likely
in the end it's a question of job (in country you want to move to), money/liquidity, and moral restraints you have.
Like e.g. buying yourself citizen ship through an arranged marriage should be something like 30k-50k€ depending on EU state, context etc. And that is if you go through organized crime rings which take a cut.
And if are rich there probably should be a lot of more legal-ish ways to get citizenship. Some countries outright allow buying citizenship, but I think besides the "buying" cost you need to be quite stacked.
And if you have good job qualifications you might get a job in the EU -> long term right to stay -> and then find one way or another to convert it to citizenship. It's probably ethically most upright but also hardest path.
But it is the daily norm pretty much in any country people do want to frequently get into.
Actually if I had to recommend anything it would be to stay very very very far away from any organized crime organizations. Doing business with them rarely ends well (as it always exposes you to them being able to blackmail you).
I guess I should have put that into the original post.