Storage requirements depend on
- whether you set it at 24/7 recording or motion only
- whether you choose H265+ or H264
- The frame rate
- The resolution you choose to record at
https://tools.hikvision.com/calculatorTool/index.html
The above is a useful url.
For example, if you have 5 cams@ 6MP resolution @ 25fps @ 24/7 recording, you will have 2 weeks: