This is crazy (IMHO, but obviously I am "wrong"). For a long time it was a typical double glazing unit, but she then got a custom made wooden door. Nice!
Even though custom made, she was not keen on me insisting on electronic locks. I am not sure why.
Anyway, I did manage to get good euro profile actual locks, hard to pick, etc, and you need a 3D printer to make a fake key! Yeh, I know!!
The problem is we got some keys, and could get more, but with 5 kids and their various family you run out, especially if any are staying with you or visiting enough to have a key.
The end result was rather annoying for me. In practice the house is never empty, but having a key in a box outside the door is not a good security measure! Not quite a key under the mat, but damn close!
So finally I got a locking spindle.
I fitted it and routed wires in the mechanism to the hinge, etc.
The mechanical lock still works, obviously.
Unless deadlocked (as I say, never nobody here), the door can be opened by using the handle inside. Yes, that too is multi-point locking, but you just turn the handle.
Now the outside handle also works, if 12V is applied to the locking spindle. Suitable amounts of super glue, etc, make it hard to dismantle and operate otherwise. The door supplier has just used a split spindle which could easily be opened with a screw driver and replaced - crazy!
But this little device was simple, and around £60. There are options for a completely new multi-point locking strip with motors in it, but they are a lot more work and cost. This was surprisingly simple.
I already had a card reader on the wall near the front door, now an NFC reader using an ESP32 (inside) to check cards. That simply set the alarm, previously, but now can be used to "engage" the locking spindle.
End result is that I can now easily allow some access at some times of day, using DESFire cards, or even just bank cards, if and when I like, and no keys in a box outside. We have someone staying with us for a few days, and they were suitably gobsmacked that I just enabled their bank card to work the front door for a few days!
I am surprised more locks are not like this to be honest. The tech is way better now, but still, it has always been so much better than simple mechanical keys.