There’s a free trial that will let you play for an unlimited amount of time, capping you at level 35 in every job/class. I’d start there if you haven’t already.
If you have Twitch Prime (which is included in Amazon Prime) they’re currently offering a free copy of the Starter Edition (base game). This comes with a free 30 day sub. That’ll save you 20 bucks. After that, if you really like the game you can buy the latest expansion for $40. No additional sub time, but it includes both current expansions. This goes on sale semi-regularly now for half off. You can also wait until the end of June and buy the next expansion for $40. It will include all 3 expansions, but again, no sub time.