Do a search on beginner or starter controller and many posts will show up. It’s a popular subject.
Short answer is that starting with budget, then choice of controller, then software and then workflow is the wrong way around.
Right order:
1. (intended or expected) workflow
2. software that is closest match to workflow (big 4 = Traktor, Serato, Virtual DJ and Mixvibes Cross, in random order)
3. determine budget
4. research controllers within budget
For software the DJ Software buyers guide is a good place to start, same is true for the 2015 Controller Buyers Guide for controllers (duh!).
Our shortlist for starter controllers looks something like this, again in random order:
* Numark Mixtrack Pro, Pro 2 or Pro 3
* Pioneer DDJ-SB
* Denon MC2000
* Reloop Beatmix 2
* Traktor S2
Of these the only one we safely recommend with Traktor is the S2, by the same token we don’t recommend the S2 with anything but Traktor. The others come with Serato Intro (light version with some limitations). Virtual DJ will play nicely with all of them too as will Mixvibes Cross. The latter being relatively cheap at 49 bucks/euro with free upgrades (at least the upgrade from 2.x to 3.x was free).