Thanks everyone for the advice. I am in two minds to look at fitting myself. I have naked VDSL and it looks simple.
But at the same time, I know how simple jobs get complicated quick... so maybe I will wait for the test to finish tomorrow and ask Slingshot how much it would cost for Chorus to fit a master splitter.
Again, thank you to everyone for your contributions and advice. This has been quite a few days of learning!