There are still stated income/stated asset programs available for borrowers with credit scores above 680.
Some purchase loans still go as high as 95% to 100%, and rates aren’t that crazy.
The “system” depends on lending. The fact is that most people make their loan payments. A certain % of defaults are expected.
Having a down payment and a crappy credit score isn’t going to work at any reasonable rate. You must have a decent score to start with, and then options open up to you, esp when self employed.