" そうです" if the answer has posited. "そうですね" is used as a prefix when you answer a questions and you agreed. 「きょうは　てんきが　いいですね」　　「そうですね」 「どんな　いろが　すきですか？」　　　「そうですね、わたしは　あおが　すきです」　( Well, I like blue.) 「あなたの　もの　ですか？」　　　　　　「そうです。わたしの　です」

These are same. But "そうですね" is more soft express than "そうです"　;)

そうですね　--> a) Yes, indeed./ Yes, you're right. AND b) Well..../Let me see... depending on the context and the situation you are in. And way you pronounce will be deferent between a) and b). In case of a), pronouce clearly and firmly. For b), you say it bit slowly and pronouce "ね" longer in a diffident manner. ・・・そうですね？--> ****sentence***, right? そうです--> Yes, that's correct. そのとおりです --> Absolutely! / Certainly! Hope this helps :-)