Under current Arizona law, you must make full disclosure to the other party and the Court. The Arizona Rules of Family Law Procedure require that everything which may have an impact on the outcome of the case be disclosed - whether favorable or not.
The idea of a trial by ambush is not permitted and your failure to disclose information/evidence will likely have a negative impact on your case. For example, if you fail to identify a (secret) bank account, and your spouse locates the account, your credibility before the Court will be compromised - if you were not truthful about a bank account, it may be assumed that you are not truthful about matters impacting your children.
It is likely that the case will become more expensive when your spouse deems it necessary to check each and every aspect of your financial history - because you are not trustworthy. Full disclosure is not only recommended, it is required under our Rules.