I am confused about the number of times the pricing usecase is called since the system initially prices the flights without a seat. How would it know what price to calculate since the user hasn't selected a seat yet?
All depends on how you read the requirements and supporting information. While I would normally agree with you on that score - that it seems counter-intuitive as to why you could price it without having selected a seat - I think there's actually a fairly clear reason laid out in the materials provided.
At least, that's how I'm finishing up my design.
Theodore Jonathan Casser
SCJP/SCSNI/SCBCD/SCWCD/SCDJWS/SCMAD/SCEA/MCTS/MCPD... and so many more letters than you can shake a stick at!