The first mistake contractors make is in assuming what the client means.
My advice, deal with your client like you don't know how to spell your name. Make sure you get a written clarification for any term that is not explicitly defined in your contract. For your potential client it should not be any diferent.
Never used analitic structure before and it is no where in the PMI "PMBOK".
Greg Akhibi
Clearwaters Consulting Ltd