For Royal Mail, if it’s important I used “Tracked”, rather than “Signed For”
For some legal documents such as letters to/from DVLA, police etc, it’s worth reading the relevant part of the Interpretation Act, but make sure you get free proof of 1sr Class posting from your Royal Mail Post Office.
https://www.legislation.gov.uk/ukpga/1978/30/section/7
Unfortunately DVLA completely ignore it for incoming mail, only outgoing.
e.g. they lost one of my V5c (bike logbook), even though it was sent directly to them via a Crown Post Office, so I had to pay for a replacement.
Re. parcels, again I use RM Tracked for sending wherever possible; my Olympus photographic stuff, they send me a DHL labels so I drop it off at a service point, after which it’s fully insured.
Simon, our local Evri courier is great, though he does always leave parcels somewhere rather than re-visiting, which I can understand having seen this BBC Panorama documentary.
https://www.bbc.co.uk/iplayer/episode/m002nnkf/panorama-evri-wheres-my-parcel
Last year I ordered a camera lens from a respected national retailer, who used a different national courier.
I bought it in a sale, but current value is about £6,800.
The contract said “signed for delivery” only, no safe drop off or re-direction allowed.
The parcel labelling said the same in several places.
Courier company advised a delivery time window, but was one of the outfits which doesn’t allow me to track their van on-route.
A little while after the window had expired, I went to the porch to check for other post, and found the lens in a box on the front step, fully exposed and in heavy rain, for all to see from the road.
Courier didn’t knock, or ring the obvious doorbell.
Fortunately lens was dry inside the soggy parcel, as the shop had double wrapped it, but neither I nor the vendor was terribly impressed.
Bill