You may want to look into running your own router at both sites, then you can iniate a link between them via a tunnel/vpn/your pick and they route between the two sites.

If your looking for tutorials, I'd highly recommend haveing a look at some videos from Lawrence Systems on how to set up something like pfsense.

I currently use thr classic "Hu seems slow, checks basic things like disk usage and process CPU/RAM usage I'll do a reboot to fix it for now".