who buys cable for spares,you looked at it because of the problems it has caused,simple as,dont pass it off as chit chat when you want answers to a problem the tat has caused,
thats what i do,sell the co and the need for a contracts,if its decent pass onto sales for contract many a time the original call out fee is credited on signing up and the upgrades and signalling etc follow,easiest customers to sell too as they know no one else could be bothered to even turn up
like lwillis says,its money for nowt and you have your foot in the door for a contract (if its decent) or an upgrade,most just want the noise stopped be it a batt change or just power the thing down in and out in 15 mins for ££
that bits out now,the one loop fits all may be a while but can see it happening im no software guru but id imagine the loop voltage will power all devices with the data to one panel or and front end pc wherever that may be
future will be 2 wire loop with fire intruder cctv all on same loop controlled by a front end graph for commercial anyway,wireless and phone apps will be the norm for domestic