Well yes, in the case of this question, having local knowledge would be helpful, at least more helpful than someone who has an (at times incorrect) inkling of life in Switzerland with no actual experience.

So since you asked:
in a previous posting, telling the bank is something you ruled out yourself.

Which leaves the landlord or the post. Whether one is cheaper than the other is only part of the solution. Is the landlord as reliable as the Post? Probably not. Equipped to forward the mail in a timely manner? Probably not. Motivated to even want to? Who knows.

Hence, I suggest the Post.

I just need somewhere to hide some gold!

Safe deposit box is an option if you can open a bank account.

If anybody can recommend any private storage facilities, unrelated to banking, I'd love to know about them.

In essence, wot Louis Wu said.

I opened an account with UBS when planning to move to Switzerland from the EU (not the UK) - move then delayed for a year or so. About 3 months ago, they introduced a fee of CHF 20 for, in essence, the admin hassle to UBS of having a non-Swiss address. But there was an exemption from the fee for addresses in certain EU countries. I remember Germany being one, don't remember the others.

I was there last week and the UBS person did comment in passing that there was now additional hassle involved with the US but I'm not a US citizen so she didn't elaborate.

Look like there are Swiss banks here that won't charge you to send statements abroad so I would investigate that.

I haven't got any deep insight into this, but my dude from the ZKB says that it depends if a foreigner just leaves CH without them knowing, then they'd be none the wiser, but they normally like a new forwarding address and they'd rather not encourage foreign accounts once people have left unless its several hundreds of thousands or a few million. This isn't ZKB policy BTW, just some info as background for the OP.

Same feedback from another ZKB person. The client was going to the US for a couple of years (work related), he was a Swiss citizen and was coming back.

He told his ZKB RM. The RM (apparently) said, "I'll forget you ever mentioned that".

UBS telling me maintainance fee depends on what services you are asking for, if you keep the ac active without having any account transfer access, then the monthly charge is as low as 3 chf.

Yes. In fact, it's even possible to have a Swiss bank account without ever having lived in Switzerland. Works just fine...

We use postfinance and they didn't have any problems when we moved to Germany or India. No extra charges or anything, even for sending the statements and whatever. Quite happy with the service. Online banking obviously a bit of a must for managing the account from abroad.