Remote Router Management

Depending on what hardware you have installed at the remote locations, you could VPN into that location. For example, I have a client that uses a Synology NAS for local backup which also includes VPN so I can VPN into that location and access all network hardware as a local user. Some routers also include VPN functionality (I have EdgeRouter Lite at home and can VPN to my home via that device). Another option to look at would be to use Pertino to remotely access that network's various devices. If your clients are getting dynamic IP addresses from their ISP, you can create an account on a DDNS provider and use that to RDP into the remote server. Many many options. It really depends on what works best for you. Chances are that you may need to use multiple approaches that will fit with your needs and the client's hardware/network...