If you prefer to make your own cables, you can choose these multicables per metre/roll. This will save you a great deal of money and on top of that, you can determine the length of the cables yourself. You should, however, consider how you will use the cables and how many pairs of cables you'd like to have bundled. If you make sure that it is in line with the multi-connectors that you want to use, you will always have enough conductors for potential extension.