R.,
I am going to be direct but please dont take what I am about to say offensively for I just want to be logical here.
Do you have "PROOF" that he is snooping in YOUR financial matters via the company he works for?
If you do not have proof it would be frowned upon for you to address what is, at this point, only your fears, assumptions and suspicions to his company or to him.
If you do address this with his company or with him with out facts and proof that YOUR private financial matters are being violated it could become a very messy situation for you and for him.
Try to keep a level head about this. Right now in this economy many households are going through financial difficulties. Please know that your finacnial stories are very similar to your neighbors.
Now as for his facebook page that is a bit of a different story. Hear me out...
It is obviously unprofessional and ignorant of him to post the client stories he comes across from work on his facebook. It's clear he lacks work ethics however again these are stories that I am assuming he has not placed factual client names to.
You could report him to facebook itself for improper use, you could print and send his facebook postings to his company with a note stating you find his remarks to be unprofessional to the clients he works with and matter should be addressed.
If you do report him to facebook be sure to ask facebook administration if your name will be left out of report.
If you report him to his company for posting privileged client history on facebook be sure to make sure anything you send them do not have your name on it for again it could become very messy if he learns it was you.
FYI: I would not delete him from your facebook page for I would want to be aware of anything that he writes that might provide me with some proof to my suspicions. Be selective in the information you share with him on facebook or directly.
Good Luck