My "figure it out later" response was more in line with paying for it. Health premiums for those who have insurance, and I'm sure we can find funding for others (those with government provided health cards would be covered). So, it's your "working poor" that would have a problem paying for these evaluations.
Personally, I don't care if people own guns. I'm not a fan of them, that's no secret. But I agree with the 2nd Amendment (although I'm not entirely convinced that the Founding Fathers intended it to be interpreted the way it is today). But my comparison to driving was in an attempt to show that things are already in place to provide "safety" to others. I know driving is not constitutionally protected and owning a gun is....but just like other freedoms, they can be limited (remember, we don't have total "free" speech either).
I guess my point is/was that if my eye sight is considered potentially vital to the safety of others on the road, then the mental health of a gun owner would also fit that standard. Again, my opinion.
As for the litmus test and requirements of what is "sane" and what isn't......that I don't have the answers to. I'm not a doctor, and I'm not insane (I don't guess.....). I would think any illness or disability that would result in someone not being able to rationally make decisions or deal with situations properly? I guess then you get in to things like "bi-polar" disorders and such.
And if what I was told is true, I'm even more sickened by our partisanship in DC. I was told that the Republicans blocked a bill that would not allow anyone on a terrorist "watch list" to buy/own a weapon in the United States. If so...WHAT?!?!?!