Reply to Cdjs 900 + djm 850 or cdjs 2000 nexus?

Hello, I live in Mexico and I've been DJing for a couple of years now but just until last year I've been able to practice more frequently because I've moved from a small apartment to a house. I don't do this for living or anything (unfortunately) but I am really passionate about it.

My current set up is 2 AT LP1240, Traktor Z2, Traktor X1 and 2 Traktor F1 (which I rarely used). I had the opportunity to play at my friend's club and some partys and while at the partys I bring my own gear whenever I've played at a Club I had to bring a Audio 6 (which I already sold), and it is always really complicated to get some decent turntables and get everything set up and lately I've been believeing that it would be better to learn how to use cdjs, since it is the club standard and also because I like new challenges. Also I'm planning to start a project with some partners that consists of a series of big parties, and by parties I mean professional djs and big venues, so I'm considering to buy some club standard gear since we plan to have different local djs playing each time, because renting it is really expensive (200 usd for the evening ).

The question I hope you can help me to figure out is is that if it will be better to go for a pair of cdjs 900 and a djm 850 (refurbished or a deal I've been offered by some store) or to go for the cdjs 2000 nexus, that will cost around the same amount, and stick to the Z2 and wait 6 months or maybe more to buy the DJM 850. The cdjs and the mixer will be for both personal use at home and (potentially) for the parties. I'm pretty sure that the cdjs 900 will be more than enough for me to practice but I'm not sure about if they are enough for the party use, the thing is that I'll be paying a lot of money to avoid to rent the gear for the parties, and I'm a little bit concerned someone is going to ask for the cdjs 2000 or 2000 nexus.

The other thing I'm a bit concerned is that the cdjs 900 might loose their value in a short period of time (since they were released in 2009) while the 2000s nexus will hold their value for some years and from my experience I'm pretty sure I'll be selling in 2 years or something like that.

So what do you believe: are the 900s enough for my needs? or are the 2000s nexus worth the money and the wait for buying the djm-850?

I hope I made my self clear, please experts help me out!