I actually disagree with previous poster re lower letterbox. Your post can then be stolen and identify theft committed. But that's just my opinion

It's also worth getting a front door with the letter box at the bottom of the door and not the middle making line of sight for any burglar difficult and even harder to use an instrument to get at your keys.

I was told security hoods fitted on doors are good to prevent access through letter boxes. They can be found at places such as b&q, SDS or online.

I have been sent the following alert from a Nappy Valley resident,
please do be cautious.

"Burglers in Wandsworth are targeting houses with upmarket cars parked outside.
The thieves push a long stick with a hook on the end through the letter box to steal any keys whether they be car keys or house keys left on a side table or stairs, back through the letter box.
They then press the fob and hey presto.....car stolen.

Two arrests have been made, yet these kind of thieves have colleagues that may carry on were others have been thwarted.
Advice from the Police is not to leave valuables or keys in a hall or on show.
In addition our local beat officer said many thefts from cars could be avoided if owners did not leave items such a mobiles iPads etc on show."