If they are in house, then theres no licensing issues at all, as cctv is only under contract for sia purposes.
Ptz and static are easy these days, via the network. They will have to have a disclosure policy, and a monitoring policy, but nothing unusual. In effect, any policy could be written on the back of a fag packet.
Put the correct dpa compliant signs up, which will let the staff know the purposes to which they are being recorded for (health & safety, crime prevention etc etc), and you are good to go.