visa registration

Question

Hi,

I have a question about registering a tourist visa in Russia that I
would be grateful if you can answer?

The facts of my trip: arriving Moscow (staying one night in hotel), the next day taking train to Vorkuta, spending three weeks on trekking expedition in Urals (no hotel), return to Moscow (for one/two nights)

My questions
- do I need to register the visa in both Moscow and Vorkuta?
- is it easier do you think to register the visa in Moscow than in Vorkuta (and how long does it
usually take the hotel to process it) considering I am laving Moscow the day after I arrive.

Thanks for your time,

Alec

P.s. I just got one response from one travel company saying "You don’t need to make registration at all because you won’t be in one Russian city more than 7 working days." This leaves me confused as I thought you have to register a visa regardless.