How Do You Validate a Micro SaaS Idea Before Building?

Hi everyone,
I’m considering building a small SaaS product aimed at helping freelancers manage recurring invoices more efficiently. Before investing time in development, I want to validate whether there’s enough demand.

What are your go-to strategies for validating micro SaaS ideas?

Do you rely on landing pages, surveys, or pre-sales?

How do you gauge if people will actually pay for the product?

Any tips for testing the idea with minimal effort and cost?

I’d love to hear real-world examples from founders who successfully validated their ideas before launch.