"I never see policemen here."
Translation:Soha nem látok itt rendőröket.
I'm having trouble understanding the placement of "itt" in the sentence. Is this the only possible position?
No, it's not the only one. Actually you could put it anywhere in this sentence (except between "soha" and "nem").
My relatives often use soha without nem - soha látok etc - is that just idiosyncratic/bad grammar?
It's definitely bad grammar in standard Hungarian, and I don't know about any dialects that use it this way.
Is there any difference between soha nem and soha sem? Soha sem látok itt rendőröket.
No difference in meaning, at least I'm not aware of any. One little thing though: "soha nem" is written separately, but "sohasem" is one word.