Netgear offers a great system for wireless security called Arlo.  These cameras are easily installed, have great resolution, offer a wide variety of options.  They are also expensive, while worth every penny, Netgear wants you to subscribe to their online storage service after spending over $350 for their system (2 camera system).  

The simple solution, which has been asked for on their support forums a number of times, is to enable the already included USB ports on the base station to be used for local offline storage.  The response to this request has been: those ports are there for a future use, which is at the present moment, undefined.  

The support forum has numerous folks wanting this enhanced functionality: https://community.netgear.com/t5/Arlo-Idea-Exchange/Support-more-storage-options/idi-p/877#comments

Netgear! Please fix this!