I have four remote sites running two vSphere Essentials 4 servers each. Each site uses Veeam Backup & Replication software to both replicate the VMs back and forth on a daily basis. Also, I backup each VM to a local Windows disk nightly. Each site has combination of about 80-100 GB of VMs each. So, I have about 400 GB of VM's to backup. The problem is we have no tape backup system in place at any of these sites. Therefore, a natural disaster would wipe us out since we have no offsite backups.
Two options I am considering are installing a tape drive at each site or going with an online backup solution. I would like to avoid having to install tape drives at these remote sites due to the overhead and work in the actual installation, swapping tapes, staying tapes offsite, etc. I have not used an online storage service, but it sounds intriguing. A few concerns with that are the costs associated with storing up to 400 GB online and also the amount of time it will take to backup over the Internet. Some of these sites have slow upload speeds.
You have provide some infor but not all. you also mentioned overhead is an issue. I am wondering how your four sites are connected. I do not see VPN will solve your issue. I am not sure if T2 or T3 is an option. I would say look for 3rd party hosted solutions and acquire your data and save it. I am assume you have tape drive at least at one location.
Backup and archiving is an art. in your case it depend how much and how frequently you need to backup data.
Also it depend how may days worth of work you management afford to loose.