Rio de Janeiro → Ilha Grande

This one is the most straightforward due to shuttle + ferry services:

• A shared transfer (van + boat) from Rio to Vila do Abraão (Ilha Grande) is advertised as taking ~4 hours (van + maritime crossing) GetYourGuide+1
• Cost: that transfer is offered starting at USD 70 per person (for the combined service) Viator+1
• Another reference says bus + ferry costs ~ R$ 70 for the ferry portion. Bookaway
• For just the boat/ferry crossing (from Conceição de Jacareí to Ilha Grande), time is about 20 minutes (fast boat) or ~50 minutes for slower boat. Just Go Exploring+2Frommer's+2
• The ferry price (slow ferry) from Angra dos Reis to Ilha Grande is ~ R$ 20.50 (≈ USD 4) Just Go Exploring

Rio de Janeiro → Búzios

• You usually travel by road part of the way and then take a boat tour once in Búzios. A full-day tour from Rio (bus + boat) is common. GetYourGuide+2Marriott Activities+2
• Example: a “Boat Trip leaving Rio with lunch / transport / tour” runs ~ 12 to 14 hours total. AAA
• Cost: starts around USD 62 or so (for the tour) AAA
• Another tour “Guided Tour to Búzios with Boat Tour and Lunch” is listed from ~$85 USD for a full day. Viator

So in practice: expect ~12–14 hours all in and ~USD 60–90 for a tour that includes transport and boat.

Rio de Janeiro → Cabo Frio

• Typical arrangements are via road (bus or van) + a catamaran/boat portion. Tours list ~12 hours total from Rio. Conozca Rio
• The same tour’s description says the road part is ~2–3 hours depending on traffic. Conozca Rio
• Cost: for the tour, it is quoted as R$ 260 for adults (in the tour package) Conozca Rio

So you might expect ~10–12 hours overall, and cost ~R$ 250–300 (or USD equivalent, depending on exchange rates and service inclusions).