I have a short set of rules that I have applied to both my business and personal life that so far (touch wood) at least has got me through just about every situtaion. I pass them on for your interest;
1) Never trust ANYTHING that comes via an e-mail - even if you think you know the company or person involved.
2) Never pay for anything purchased online if the company does not accept PayPal and/or asks for the security code on the back of your card. Again I have been with PayPal in both business and personal transactions for well over ten years, and only once had a problem which was covered by their insurance (free) system.
3) Pay for all utilities through direct debit with your bank.
4) Yes, I DO have two only exceptions to this a) Amazon (both ways) as they are both source of product and payments of my Royalties, and have been for several years, so I am pretty comfortable with them. The other is restaurant payments, although I do recognise the risks in this area.
It isn't total protection but it goes a long way towards it.
When I was a Marketing Prof. I made a constant reference to the fact that (as I have said earlier) that Banks are NOT your friends nor your Business allies but simply Commercial enterprises out to make a profit. They do have certain regulatory obligations above and beyond most others, but for the most part these are related to opening accounts and proof of identity in certain transactions. Beyond that they are strictly commercial - notably in the realms of insurances.
We need to protect ourselves more and more as the internet takes over our lives. Although unavoidable Government information is also seen by a myriad of people, many of quite junior rank, but I suppose you have to trust some areas - although if I was Greek I think I would not believe that!
What's the term 'due diligence' or 'caveat emptor'? - Probably both.