Both cities are worth visiting. very few people speak English in either place, but you will be OK regardless. Air travel is relatively expensive in South America so try to get both destinations on one ticket. Friendly Apartments offer great service but they have become very popular so during the high season they are not always able to offer a wide selection. I have had very good experiences with them though so it's definitely worth checking what they can offer you. I believe they mauy also have some apartments in Rio. Also check with Carlos Contini. I rented from him on my last tip and he was very attentive and professional. Highly recommended! His email address is [email protected]. Send me a PM if you want me to make a personal referral for you since I have good relationships with both of these agents. Not sure if it would make any difference or not, but it couldn't hurt.