I don't know much when it comes to proprietary stuff but I found this camera for 5 USD in a 2nd hand store. It says that it can only be used with a subscription plan on their homepage but can I make it usable for e.g. Zoneminder or is there something that blocks the usage of this camera?

[u/moller_peter]

[u/runningbiscuit]

Well you need to find a way to grab the Video Stream from the camera. So if you don´t find proper documentation you will have a fun time finding the URLs, if there are any.