Don't worry—I won't preach to you how much it's worth it. It's a personal decision, one that must be made according to your individual financials. Or perhaps according to the availability of decent facilities in your area. I am, however, going to preach that you don't need a gym to work out.
There goes that excuse, right?
Here's a handy infographic for those of you that don't have access to a gym. It's a great 30-minute workout that doesn't require any equipment, except maybe a chair or a bench or step which should be readily available to you. If it looks too intense, you can modify as needed (as always).
You can find more bodyweight exercises at Greatist.com...seriously, if you haven't checked out their site yet, you totally should. Such useful (and interesting) info.
Question: What's your favorite bodyweight exercise?