"Where are you? (complete the user profile and at least tell us what country you are in)"
Sorry, I'm from Hungary
"Is cell service even available at the location(s?)"
Yes, cell service is avaible almost everywhere in my country.
"Is this location(s?) "off the grid"?"
Yes, it is a weekend house in the middle of nothing, with no water, no electricity.
"How far away is it? Line of sight?"
60km from me. That is why I though the internet as a solution.
"Are other solutions available (APRS, etc.)?"
I don't think so, but I'd like to solve this challenge with arduino
Any comments are welcome