Other than the cost of the actual plane ticket, what other fees apply? Would I have to pay a fee since I'm a minor, and how much would that be? On average, how much would I have to pay to check baggage? What are the fees that aren't included in the ticket cost? And how much money should I have with me to ensure I can get on & off the plane both on the departure flight, and the returning flight?

What is your starting point (city, country)?

The price will include taxes, and other airport fees. Those are often listed on the price but not always, esp if they are advertising super cheap flights.

Also be aware at 16 you can not get a hotel room. Sine the min age is 18.