: Use a small "Room" or "Plate" reverb. Avoid large halls; the goal is to sound like the artist is sitting right next to you.
: Most producers require you to include "(Prod. [Producer Name])" in the title.
: Use a "Wow and Flutter" effect or a vibrato plugin to simulate a degrading cassette tape.
: "Free" usually means for non-profit use on YouTube or SoundCloud only. If you plan to put the song on Spotify or Apple Music, you typically need to purchase a basic lease.