Hi @Nicolas2436 I have a MasterLock electronic lockbox. https://www.safe.co.uk/products/master-lock-smart-key-safe.html It's meant to be remotely accessible, etc, but I've never been able to get the phone app to work. Plus, customer service is in USA, zero help in UK.
Just saying, in case you were considering this product. It's great in itself, if you don't attempt to change the access code and just leave it at factory setting code. It has never failed (but you need to remember to change the battery regularly and pre-emptively).
Never had a security problem in keeping the same access code.