You can say something like "I look forward to getting to know you" or "Thank you" in a positive answer. "I believe we will get along well." In a circumstance when you don't believe this connection will work out, "Thank you" will enough. There's no need to tell them how you feel about them right now. It's better to let them down easy and avoid bad feelings. In the context of social interactions, to say that someone can be your friend means that you would like to see them again under different circumstances. You are indicating that you would like to continue seeing them as a friend even if they can't give you their full attention right now (for example, if you were roommates). Generally, people like to hear that you hope they will become friends with you. However, it is not necessary to say it directly. You can also indicate this by using some common phrases such as: "I'm looking forward to meeting him/her," or "I think we will get along well." People usually say things like "I hope we can be friends" as a way of saying goodbye or wishing someone good luck in a future interaction. This phrase is used when you want to show that you are still interested in what kind of relationship there is between you and this person.