Do you plan on using these points to watch different channels in each room at the same time ? Will there be occassions where you will be watchin 4 different channels on your 4 tv points at the same time ?
if all you want is to distribute the main channel from NTL to the 4 points, then it should be easy enough, and no additional rental afaik, just using a plain old splitter box on the coax out of your NTL box, or better still, one that will allow you control the box also from the other rooms.
Wexfordman