Price for competitive value, start where you think, but - tier it to bundle of users at least, so as more users are added any additional effort on your part ha

Price for competitive value, start where you think, but - tier it to bundle of users at least, so as more users are added any additional effort on your part has financial cover - think about support, customer success, installation, upgrades and ensure your including that - test the number with them. Negotiate. Caveat - this is limited advice use at own risk etc etc