Donnie – you had mentioned about DJing in your home with headphones & that you’re looking to pick it up as a hobby. At that point, I’d have to agree with DJ Vintage 100%. Get a starter controller, learn some basics, and have some fun.
At some point, you might have other plans. Let your equipment grow with your plans, let your music grow with them as well. One thing I struggled with at the beginning is trying to be prepared for everything. Depending on where you progress toward, some equipment is better to have than others, some music is better than others.
As for Spotify and DJay… as long as you’re in your home practicing, you can pull it off. Spotify isn’t the golden ticket, but it’s a tool that you’ll find useful and especially during practice. Once you get your rhythm down and you get some plans/direction, then start looking at DJ pools for your music. They’re mostly cheaper and legal for public play, and you get to keep what you do pull down from them. I’m a mobile DJ so I have to keep a diverse library of music but if you find a niche genre you like, start with one pool that has a bunch of music from that genre and grow out with other pools from there as you see fit.