For us (Dependabot) the best advice I ever got was that your initial customers should come from sales, not marketing, even for a really low-price SaaS product. I was literally giving Dependabot away for the first 6 months of its existence, but I was still doing concierge sales on it.

When you sell to customers directly you get to hear their reactions and get a much better sense of what's valuable to them. You also make yourself more approachable if/when they've got feedback down the line. Finally, you get a predictable return to your effort (even if it's low!), which prevents the kind of boom and bust that can burn you out in the early days.

I'd really, really highly recommend anyone else looking to start a B2B business take the same approach, even if your product is way too cheap for sales to be scalable.