This huge volume of data is the equivalent of more than the combined storage of 175 iPhones, each with the maximum storage capacity of 512 gigabytes.
“How do we make 80-90 TB sound like a lot?”
Cheapest drives I can quickly find are 4TB WD Blues for €80. So that’s €1600 for 80TB, plus a computer to control it all… $3000 is probably a good estimate. Nice work.
TBH server class storage can easily come in at $100/TB/year, once you factor in all the costs, including the RAID media, the frame, electricity, backups, data center rack space, the cost of operator management, and maintenance. So 80-90 TB would cost $8-$9k annually (plus additional costs for downloading the data, which most online storage providers charge.)
Given their rental rate of ≈$80k, storage is probably around 15-20% of the total rental.
It’s also possible that the rental rate varies depending on the retention of the recordings. Most places don’t keep ordinary security camera footage for more than 30-90 days or so (not counting saved events that they’re preserving as potential evidence.) So you could probably cut those costs by quite a bit.