Here you just go to a provider store, we have MTC, Megafon, Beeline, TELE2, and now Yota. You bring your passport and buy a SIM card for 3 bucks. Then you stick that SIM card into a phone you have or you buy, and if you buy a phone it will not be carrier tied. By the way that 3 bucks they put on your balance, and you pick your calling plan, etc. For normal usage it comes to about 5 to 10 bucks a month. You also with some plans get free calls between same carrier numbers. Internet costs 5 bucks a month. When your balance gets low you just go and put some money on it, either online, or in bank, or street terminals. There is also a promised pay feature, when you get low, you dial a code and get credit.
Phones start at 8 bucks, that's with a SIM card included, and a special calling plan, and you get that 8 bucks on your balance, but the phone is carrier tied. Prices for phones are same as everywhere, but there is no carrier tied phones, they are all, 98% of them are unlocked.
You can also pay more and pick a beautiful number, prices start from 8 bucks and can go as high as 300 bucks for a specific pretty number, something like 555 5555.
Most of us have at least 2 numbers, usually MTC and Beeline, or Megafon. We stick it into either different phones of into one phone with 2 or 3 SIM cards. That way calls between same operators are either free of cost low. Personally I don't cary about my phone bill, it never gets high, it is always low, I just have 4 SIM cards and phones because I think it's cool.
I remember ATT bills in Miami and we'd pay like 120 bucks per months for 3 phones and calling plans. Crazy.