We will be leaving to go on this tour in about a week. We are adding time to both ends of the tour and will need to do laundry at least once. Is there a place to do laundry in Tallinn or Helsinki--or both? I am not into the "wash in the sink" routine. Too much trouble!
Are you taking Rick's guidebook with you on tour? I recommend doing so. In Tallin, he describes Top Clean and Pesumaja Sol, both with full-service options (see p. 655 of Scandinavia), and in Helsinki it's self-service at PesuNet. Your hotel staff should be able to recommend other options, if those are not close to the hotel.