I have just ordered VM for a new broadband connection with the quick start install.
However, I have now realised that there is not internal socket in my property, but a coax cable coming through the wall to a splitter which was used previously. This cable seems to come from a larger splitter in a communal service cupboard with coax and telephone cables labelled for each flat.
I’m unsure how I can attach the isolator cable to this -do I just connect the cable directly to the modem, rather than using the existing splitter or the included isolator cable or do I need an engineer to for an internal socket?
You should be able to connect your cable directly to your existing splitter at one end and then the modem at the other end. You don't need a socket nor any other splitter you have been sent unless you have additional connections to need to make. Most people only have 1 or 2 devices so one splitter is plenty.
that will let you connect the isolator cable - removing splitters will have an effect on the levels to the hub - downstream should be within -6/+10 - if you are in that range without the splitter then thats ok
If you remove the splitter you'll need to purchase a coupler like stated, but if you leave it in, you can just connect to it. If the previous occupant used it then the levels may be set to include a splitter and removing it might mean that your levels could become too high. I'd just connect to it to see how it goes. If your happy with it why buy stuff you don't need?