Ehh, probably wait. I'm surprised that there wasn't one this last week/weekend, but around this time of year (from about now to around Christmas, barring patch releases), CIG tends to do some Free Fly events. You'd only be required to make an account and pay nothing, and you can download the current patch (2.6.3) and play to your hearts content, unless the servers say "no" (networking problems will be fixed in a future™ patch, supposedly 3.1). Probably by the end of the year, patch 3.0 will release, and I would expect a Free Fly event with that. A lot of people want to consider 3.0 the start of beta, but that would likely be the end of the 3.x patches.
At the moment, there's dogfighting, fps, a few missions, some space stations, and a small chunk of a star system available. No persistence yet, but that is going to be part of the 3.0 release. 3.0 is supposed to include planetary landing (currently only moons), some more moons added, character customization, new item system, some more missions, cargo stuff, some more ships, some more fps stuff, performance improvement (NOT network), and some other stuff (old post, but most of it is still there).
Right now, they're in the process of bugfixing to get it to a releasable state for release. https://robertsspaceindustries.com/schedule-report
Don't bother putting any money in unless you're confident that you're willing to wait for eventual release without getting cold feet and requesting a refund and really wanting to keep playing the development patches. But even then, at least wait for a free fly event first.