We're planning on a freemium tier in the future. Promoted is more useful for bigger marketplaces because when you're small, simple heuristics will get you far for free, and you don't need the dedicated infrastructure, support, and complexity management that we offer. Also, +9% is astronomical for large marketplaces but not notable for new ones.
$30k/mo minimum is roughly the cost of 1 FTE. If you're big enough to start hiring a team of specialist roles just for search and ML, then we're a better fit today.
Email me at ayates@promoted.ai, and let me see how we can help!