Honestly, selling your controllers and going for CDJs if you are on a low budget is a mistake.
The most affordable way to DJ is digital, but in no way do you need all that stuff.
Honestly you can do more with just the Mixtrack pro that with that CDjs and the mixer.
I would try to get at least a semi decent laptop that can run either Serato, VDJ or Traktor smoothly. Even most i3 processors can do that and just make sure you get 4 gigs of RAM.
The N4 is pretty decent controller wise and I am sure you can survive without the NDX400s just rip them CDs and play it on the N4. It is really easy to carry an N4 and a laptop in a single backpack even on a bus or train.
Stay away from the Behringer controllers, yes they are cheap, yes they might look cool in theory, but in fact they are really bad.
I see ZERO pros to CDJs in your price range over digital. There might be some things CDJs have going for them, but then you are looking into an investment of about 4000 bucks or more and you will never carry this around easily.
Also you can train everything on a controller. It is not like if you ever get into a club with a CDJ Nexus setup, you just have to take a look where the buttons are, new CDJs are just like any controller out there (just loads more expensive and have obsolete CD slots).
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