Yeah, I remember when it was $75 but didn't jump on it then. Back then I didn't think they'd ever charge for basic functionality that was offered for free for 10 years. I don't regret not getting it though, this is the kick I need over to Jellyfin.
Let's Encrypt supports DNS verification, if you have access to update the zone file. It makes automation harder, but there are scripts to do the DNS update for the verification.
DENIC doesn't even report domain expiration in whois data, which is super annoying. I guess you pay per month technically, but was new to me for a project to monitor a whole bunch of domains for renewal.
If you can sacrifice quality, you can encode the videos at a lower bitrate, but that is lossy compression, not lossless. Also, if your videos are in h.264 codec, then transcoding them to h.265 and preserving the quality may be a way to get the files smaller. You would use a tool meant for video, like Handbrake for this, and not winrar or other generic compression tool.
Why would you want to shoot yourself? Don’t do x.