if you want to make money off of software you don't make it open source
what some people do, and I think it's the best way to make money off open-source stuff, is have your free software, but have extra services related to it that are not free. like, having people who will set it up for you, or commissions to make custom plugins, or hosting it for you so you don't have to, stuff like that
but making you pay for the software itself, I'm not a big fan of that