Until AI isn’t trained on all open source code ever written, regardless of license, which I doubt will ever happen, isn’t SaaS-writing AI in some sense building a larger scale & more concentrated version of what you’re hoping to destroy?
Personally, I hope and want everyone selling used cars and life insurance to be honest and upstanding. some of them are.
If you absolutely can't trust any SaaS it is equivalent to you cannot trust any vendor to do anything as they may fuck it up. You can solve that with DD.
Obviously a false dichotomy for most real life scenarios but the point being that I'd rather do it myself (any which way) than trust a bad developer, doubly so for customer-facing operations.
If there's another provider offering that function, sure, but let's talk rupees.
Also, the used car market is much more efficient than the new car market. You are a lot less likely to get ripped off, believe it or not, when you buy used. It is also three times as large as the new car market, with much lower barriers to entry and no manufacturers carving up sales regions and limiting dealer franchises in each region, and penalizing vendors that sell outside their region, e.g. creating little local monopolies. Every used car dealer has to compete with carmax and carvana and hundreds of other used car dealers that have access to the same pool of buyers and sellers. They have to fight for those buyers and sellers. That's a very different situation than the four Toyota dealers in your metro. In fact the reason why Toyota dealers are especially bad in terms of ripping people off is because the Toyota product is so good and you have to go to them to get a new Toyota. But if you want a used Toyota, suddenly have 10x the options, and not one of them has a monopoly from the manufacturer.
Not saying there aren't bad apples in used car sales, but it's a lot harder to survive long term on shady practices than if you are backed by a major manufacturer, have exclusive access to sell their cars, and also exclusive access to do recall and warranty repair. Those types of monopolies can prop up all sorts of bad practices.
My reality: I use my bank's car-buying service and pay the bank's negotiated price.