This is largely why I built Nodewood [1]. Every time I wanted to start a new project, almost always a SaaS idea, I'd skip over the "boring stuff" like building user management, subscription management, teams, admin, all that, to get to the meat of the business logic, to make sure I had a valid idea. But I still needed all that stuff eventually, so I'd have to lose time later building it all in!

So I decided to just build it all once so I could re-use it, and then I found that others had the same problem and are happy to pay a reasonable amount to have it solved for them, and now it's doing pretty okay for itself.

It did end up taking a lot longer and involving a lot more work than I expected, but I figure that's alright, it just means a more-reliable base to start from each time.

[1] https://nodewood.com