Right now Dynadot has the cheapest first year at $1.29, and NameSilo the cheapest renewal at $10.95. Over three years the lowest total at one registrar is $23.27 at Dynadot.
Why does .sbs cost more after the first year?
Many registrars sell the first year below cost and recover it at renewal: at Dynadot, .sbs renews at $10.99 after a $1.29 first year. Compare the renewal and 3-year columns before you buy.