With MaxDrive canceled this is important.
If the camera (w/ tiny $5 SD Card) could be configured to FTP video’s when writing the file is complete,…
Most off the shelf NAS Drives can be FTP’d to, Cloud Services can have FTP configured, You can even install a FTP server on an old phone, tablet or laptop.
Currently (if 24/7 recording is desired) people are buying in for $20 and to get a reliable grade SD card with enough space for 7-14 days; spending another $20-$40 on top of that for a solution of $40-$60 per camera.
5-10 cameras and you are in the $400 - $600 range for a 24/7 monitoring solution.
With FTP like I’ve described the solution, the total cost would be $125 - $250