All I want is a dead easy way to make a landing page + account + payment options for a tiny prototype SaaS like this (e.g. I supply a few APIs as 'backend' and the rest just works) -- quite similar to the One Item Store the author made. I can only imagine how many people have had to repeat all the same boring steps for some small proto.
Hey have you tried/considered BulletTrain[0] or lemonsqueezy[1]?
I also have something that I'm working on for this -- I've used my tool (which isn't productized yet, it's still ~4 templated repos) to launch 2 projects (in bio) so far and am working on a third product, but BulletTrain/lemonsqueezy are two much more polished options I know about -- maybe you should give them a try?
Is the thing you're trying to sell an API? Or is it a resource-provisioning sort of SaaS (they sign up, you spin off a persistent worker or something). I model them as the same in my thing (the provisioned "resource" is the API key), but I think that's one of the big differences in which tool will work easily for you.