I might be slightly biased as i've owned them before but why not CDJ 400's
I was in a similar position to you wanted some CDJ's and didnt have the cash for some 850's or better. CDJ 400's feel better than the 350's to me (IMO) and have a better build quality, They also take USB (Not rekordbox though). see if you can find some on your local gumtree and test em out. i recently just sold my pair with a cofin flightcase for £550 , So they are definilty within your budget.
As far as the mixer goes for your budget i would reccomend the Behringer DDM 4000, Great 4 channel mixer (again could be biased as ive owned it?) i picked my one up for £100 and it was in mint condition. xones and DJM's are brilliant mixers but wayy put of your price range tbh.
Hope this helps![]()
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