If the latch is sticking you can try taking the handle off via the other posters instructions and lubricating the latch slide in the door with a graphited lock lube like https://www.agscompany.com/.... If this doesn’t work replace the handle.

Does your use case include random people on the internet accessing these services or is it just for you? If it’s just you and a couple friends and their devices look into Headscale

If you're on city water that doesn't lose pressure during power outages they also make water powered sump pumps.