1. Follow him, pretend to meet him or ask him something in a place you think is more suitable, so as to get in touch with him.
2. Write I want to know you on the note in the old but practical way, then slip it to him secretly at the right time and run away. Sure, write your contact information on the note. Boys are generally curious, so don't worry that he won't contact you after the note is sent.
3. Looking for a friend of yours is bold, of course. Let TA inquire about the handsome guy and get his contact information, then you should know how to do it.
Most boys will be soft-hearted when they meet girls, so as long as you seize the opportunity, that boy will definitely respond to you.
I hope the landlord will take good care of it!