DO NOT PAY CASH FOR A TICKET!!
Bad experience happened to me about 5 years. Friend of mine bought a car in Miami, FL because of a family emergency he could not go day of flight. Told him I would help him out and go. He gave me $1,000 cash for the flight that day. I didn't want to keep that much cash on me so paid for the one way ticket in CASH at airport (back when they took cash).
Went to security and must of threw up a red flag because I was never so intensely searched in my life. They took me to a room and was asking me why I paid cash for a one way ticket. (and i understand why). But for an entire year after that i was "randomly selected" every time for additional screening.