Getting into SWADE and starting with Deadlands - Question

Hey: I'm going to be starting to learn the system because I have a player group really interested in Deadlands, but I have never run any SWADE system before. I am aware that it is *better* to own the Core Book along with the Deadlands material.   But in the interest of cost outlays, do I *need* the core rules in order to run it initially, or can I get away with the Deadlands-specific materials? I'm not cheap (my Roll20 ledger can verify that), but the holidays always have me cash strapped and I'm trying to get away with the minimal expense needed to start. Thanks everyone!

it's not difficult to run even without any of the compendiums or modules, but they do make it easier. it is also made easier with the dealinit api (which is one of the ones you can install via the roll20 built in api list, as long as you are a pro member) but you don't really need it either.