Cambodia EB visa 6-12 months extension

Hello  Expat.com 👋 i want to move from Hungary to Cambodia within a month or two. I am not retired yet so the EB visa is my option. I would sell my house here and would like to move to Kampot long term. The only thing that worries me and is not clear to me is that I heard that they ask for a work permit / employee letter - in order to extend the business visa for 6-12 months - and I have $150,000 with which they could rent a one-room studio apartment but I do not have a Cambodian work permit .. if someone could help clarify this matter I would be very grateful because at the moment this is the only thing that is holding me back and forcing me to hesitate.