Sorry, I don't have any experience with getting your legal fees paid, but I'd imagine if you had to hire a forensic accountant to find money he was hiding you'd have a pretty good chance of getting some legal fees covered.
As for the Costco card - what does the membership cost, 40 or 50 $ a year? IF you renewed your membership after he moved out, ignore him or simply point out that now that you are separated you each need your own account. If the renewal was paid out of community funds just send him s check for $20 and say here's your half of the renewal fee back. Silly I know but pick your battles.
If you don't have a credit card in your own name I suggest you get one now. If your joint cards are in his name with you added on as a user he could take you off them (although I'm not sure how that would affect your liability for that debt.)
If you have frequent flyer miles or other rewards on those credit cards remember they are an asset too.
You're wise to keep these things as much as possible in the lawyers hands. One thing my ex said to me as we were going through this that I think was wise, something to the effect of "if we both think we lost out it's probably an equitable division ". (Words somebody must have told him because he conveniently forgot them later),
Try to avoid appearing adversarial, just say "yes unfortunately it costs more to live apart" and "Im only asking for what the law dictates" and leave it at that.
