I've recently been asked the question, what the lowest level someone could build a liquid pain hospital. For a jumping off point, let's assume there is one PC who wants to establish this hospital, and wants it to be able to be run by a small group of Experts. The obvious class choice for the PC is Artificer, as they have the best ability to craft the magic items needed to make the hospital function.
So the question before the board is what magic items would be necessary to run a Liquid Pain Hospital, and we'll extract backward a level requirement.
An ability to cast Liquid Pain (BoVD p98) is a obvious must.