What do you need? You need lots of perseverance; an ability to be brutally honest with yourself about your own work; huge amounts of patience; and a determined, disciplined work ethic.
First, make a decision about what you want to do. You said that you want to make shorts. That's fine, but why do you want to make shorts? What are your goals? To write? Direct? Be a DP/Cinematographer? Editing or CGI? Something else?
My feelings are that your goals define your tools. Once you've decided what you want to do you can begin to make your purchases.
Now, assuming that you want to direct...
I'm one of those old fashioned types that sees the merits of "working your way up the ladder" and "paying your dues." How many film sets have you been on? Even crappy, no-budget sets count. So get out there and be a go'fer, a PA, a runner - any job you can get. Because what you also need is practical experience and, just as or even more important, a broad network.
I know that many on IndieTalk are opposed to this view of working on other projects before beginning your own; they feel that you should jump in feet first. And that may work well for some people. But my position is that you can observe the mistakes that others are making and then, when working on your own projects, not repeat those mistakes.
The difference between a hobbyist and a professional is that a hobbyist learns from his mistakes; a professional learns from the mistakes of others.
What will (hopefully) happen is that you will build a network of people with whom you like to work. Many of those people will probably have equipment - so now you don't have to buy any gear at all and you can rent those few things that you need to fill in the gaps. And, since you have been paying attention when you worked on other sets than your own, you've learned how to avoid the worst mistakes, and learned that you need to preproduce the crap out of your projects, and then preproduce some more.
By running an efficient shoot your people stay motivated, and when people feel motivated they give you better work. And, since you haven't blown every last cent on gear you (should) have the money to treat your cast and crew reasonably well - and people who believe that you are looking out for their welfare will work hard for you.
Anyway, enough rambling from old Uncle Bob.