Hi mzagas,
You haven't said anything about your level of experience, your background, etc. nor have you said anything about how you plan to use the tools nor anything about the genre(s) you plan to work in. Similarly to what jude77 said, your particular "biggest bang for the buck" could easily be completely different than someone else's.
If you are a programmer with spare time, for example, then building your own stuff should obtain you the biggest bang for the buck but could also be horribly inefficient. If you're not a programmer or don't have spare time, this isn't even conceivable as an option.
If you plan to perform, then you don't need many if any synths. If you are into EDM, you'll almost certainly want to have a lot of them if not a couple of very powerful ones, the choice between these two options depending on how you like to work.
There are so incredibly many options that it's impossible for anyone to give you a good answer with any real assurance. Also, you may very well have narrowed down your choices prematurely, but that's also impossible to know without information about your background and goals.
If you've just decided to jump in and try a bunch of stuff out, then I would say just get a copy of Computer Music Magazine with a DVD and you'd have a lot of pretty good stuff for almost nothing. Download evaluation copies of several DAWs and have at it. Save your extra cash until you really know what you want, otherwise you might well regret having spent so much with so little to show for it.
Good luck,
Dave Clark