You can remote into a Windows 10 Pro computer for free. Easy to upgrade any Windows Home to Pro and does not require reinstall. Pro features just get instantly unlocked. Windows 10 Pro has Remote Desktop Protocol service built in.
- Needs either static IP from ISP or use cheap or free dynamic DNS service like No-IP.com
- Open and forward port 3389 TCP on router to point to internal IP of Windows 10 Pro computer
- Enable RDP login on Windows 10 Pro computer
That's all you need. Then you can remote in using RDP client app and point to your ISP static IP or Dynamic DNS name you set up. All free. Login and connection is encrypted automatically. The RDP remote experience is second to none. The computer running RDP client does not need to be Windows Pro, it can be Windows Home or even a totally different OS like Android with one of several free RDP Client apps.
Depending on how critical it is or not to eliminate the possibility of temporarily loosing access, you could forgo the dynamic DNS service if you don't have a static IP. The reason being that from my experience dynamic IP addresses from ISP companies seem to stick around for a long time without changing. I've had the same dynamic IP for over a year now. So you could just open and forward the port and turn on RDP access and then be all set and just use the dynamic IP address you got assigned to remote in. If it does change one day then you just need to find out what the new IP is and start using the new one but that requires being there to find out what the new IP is. Up to you. But setting up the dynamic DNS service and then running the app to keep it current shouldn't be too hard.