It's as simple as that. You need to feel comfortable with them and that is achieved in the way that they sell/present themselves. 'Interview' 5 of them. If you instantly like one, go with them. If you don't like any of them, interview more of them. Look for the 'getting along chemistry' and of course if they have a good reputation, all the better.
If you suspect that she is hiding money, unless we're talking HUGE sums, just let it go. Don't even think about it. The cost to reveal it and split it just isn't worth the heartache and a quick read through your sitch tells me that you've gotten plenty already.
Honestly, making an issue of her hidden loot is just gonna cost you more in terms of cash, toll on health etc.
If she's wanting to go mediation, go along with it. Your goal is to get out of this unscathed so that you can rejoin the real world as soon as is humanly possible.
