Just thought I would mention since I don't  often mention it but we also install Yale alarms you have already bought yourself.

I fitted a YALE 6400 system for a client Yesterday as he had got into a slight muddle and was having difficulty programming the system and  drilling the siren holes.

With our extensive experience we were able to help.

I arrived to find an embarrased gentleman with a wife who's look seemed to say 'I told you you should have got someone in'.

Never mind the cavalary had arrived and the alarm was duly installed without any further ado. The client was fully instructed to its use and everyone was happy. For only £20 I also added a second working siren so now he has audible deterent and flashing lights on both the front and rear of his property. He was very pleased..(as was his long suffering wife...:) ) and he even gave me a £10 tip... A happy day all round.

http://www.fastalarms.co.uk/yaleinstall.htm