The Mystery Of German House Numbers

A thing I've never understood here.  

There seems to be no rhyme or reason to it.

In the UK the convention is to give the house nearest the central post office the number 1 and opposite is the second .  Next to 1 is number 3, and next to 2 is number 4 and so on.

Not here.

I have no idea what happened to numbers 21, 23, 25 & 27.

I live in a terrace of 3 houses.  Opposite us is also a row of three houses.  Opposite are numbers 19, 21 & 23, whereas we are 10, 10A & 10B.

It makes no sense.  To me.

I learned today that I need to register my drone with the appropriate civil service department (can't have too much bureaucracy) and I also need to have it added to one of my insurance policies (more form filling).

When that's all finished I expect to take lots of Blips with it.