How much would 24hr security cost a year, £60/£70k? (Complete guess)
I'd guess at around £150,0000 just on staffing costs. Three shifts every day, two people per shift. Then when you factor in all the other costs - maintenance, insurance, transport - it starts mounting up real quick. I just don't see that kind of money ever being spent. I certainly don't see people paying in sufficient numbers to put a dent in the costs.