What costs should i aspect for two people a day?
Depends on your accomodation & how long you’re staying there, how much you eat at restaurants vs buying groceries, where you buy groceries, how frequently you go out for entertainment..
Use numbeo.com to check and compare costs of living.
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1 solo travel can live and travel very uncomfortably on $100 a day in Russia.
The good news is that you can reserve hotels the day before and you wont have to pay extra.