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How expensive is the renting of scooters or boats?

scooter about $2,5 per hour; electric scooter about $7 per hour; SUP about $20 per day.

Yes, it's St. Petersburg! Thank you:)

I looked up the Karpovka River and thought as much :o). But I didn't know if it's ok with you to mention the city.

I usually write the name of the city at the end of the post so readers don't get geographical confusion, but this time I forgot. Yes, it's St. Petersburg, Russia.