There has been a spate of thefts by some 'not too bright' thieves. They are taking scrap, batteries, copper etc while leaving generators and inverters behind. A friends house had all the cabling and copper pipes and taps stripped out. Caused a lot of damage breaking in, 100 times what they will have got for the scrap.
I've moaned on about this before but - GET AN ALARM!
Get one that phones a neighbour, they start at £20 and one that covers everything for about £100.
Rejas and fences are useless. If your house is off the road and looks like it might contain anything pinchable then you will be a target. Please be prepared.