thanks for the quick reply and the info. I am based in Cleethorpes.
the main unit is an LJD Deltawave with CD recorder. It is installled in a garage at the moment, and the room it is going in is directly the other side of the wall, so i can use all the existing wiring routes.
He currently has three cameras, all dome type, will have to check which models. One of them has Pan andd Zoom working, but he's had a conservatory built, so I need to move that camera and will need to extend the wiring. The cabling looks like it is just co-ax, so I'm not sure how the PTZ works as I assumed there wouldbe a separate control for that. Having said that, I couldn't get right behind the unit for a full look.
The other two cameras are both the same type, and are supposed to be PTZ, but apparantly that never worked. One of them produces images that are almost unviewable because the sun has made the dome go 'cloudy'. So he wants them both replacing.
The frontage of the property is about 50 feet, covered by those last two cameras and the boundary is about 15 feet, so i think they must be wide angle.
I'm only guessing here,as I have no real experience, but as he has a spare channel on the main unit, I think he would be better having static cameras at the front recording the entire frontage and ideally a tracking camera to get better pictures of moving objects 'just in case', but I'm not sure which ones would be compatible and how much they would be likely to cost.
thanks for any help,
andrew