To post a set of house keys to the address they belong to?

[familygermsareok]

Would welcome opinions about this. A family member has recently sold a house they inherited. They have now found a spare set of house keys among some of the clearance items. It is too far away to hand them over in person. They were just going to post them to the house under 'signed for' delivery, reasoning that they would be traceable and would need to be signed for by recipient so should be safe enough. They have disguised them in cardboard so it is not obviously keys.
I have reservations. I'm not sure I would be happy about someone posting keys that open my house to my address. If no one is in at delivery what if postie asks a neighbour to sign for them? Or even if they go back to depot to await collection they are still going through a longer chain of potential contacts.
I have suggested writing to new owners and telling them about keys, asking if they are happy to have them sent there or to another trusted address.

Am I being a bit over-cautious? Signed for delivery might well be reasonable but it just feels wrong to send keys to their own address

I think you're being a little over cautious if I'm honest. How would anyone know that they're keys if they're in a box? I'd let her got on with it

Are they some kind of fancy complicated key? If they're just standard chubb or yale then l'd probably just throw them away. They cost pence to copy so not even worth the cost of a stamp. Do you have an email address for the new owners?

Presumably they have some kind of way of getting in touch with the new owners. It would be safer to get them posted to say where one of them work - if they'll give that info...

I wouldn't bother - there's every possibility that the new owners have had the locks changed, anyway.

Many people change the locks anyway when they buy a house so your gesture, kind though it is, may be unnecessary.

My mother recently posted me my keys. I really did not put this much thought to it she put them in an envelope and posted it job done.
But unless they've asked for them I'd just bin them tbh.

Couldn't the estate agent pass them on? Just post them to the agent.

Agree that they may have had the locks changed.

Otherwise: so long as the address they belong to is not actually printed on the key chain or something I really don't see the issue. I'm notorious for losing my keys and will be forever grateful to the hotel that managed to have them in my letterbox before I even returned from the trip during which I lost them so that I could actually get into my own home upon my return ...

Something a bit like this happened to us.
I would contact the Estate agents who sold the house.
They would probably have email contact details for the new owners and could get in touch with them about the spare set of keys still in your possession.
This may make it more "official" than just posting.

Thanks everyone. They are just bog standard fairly old keys, nothing special. There were only a couple of sets with the house so my relative thought it might be handy for them to have another, but on reflection, it is probably as cheap for them to get another set made as it is to post them. And of course they may well change locks anyway, hadn't thought of that.
No email address, only the postal one. We did think of sending them to the solicitors who dealt with the estate and sale but as its all settled now thought they might charge an extra fee to deliver them.
Looks like I was over thinking it, but just binning them sounds like it might be the best solution anyway