Required parts and best practices for D-130J roof installation

[harjotsandhar]

Hello everyone,

I've been away from scanning for far too long, and have spent the past few weeks doing the research to get me back in the game.

I have someone coming over this weekend to install a D-130J antenna for me on the roof, and neither me, nor him have done anything along these lines before.
Can I please get your input on the questions (related to the parts I need to order) listed below so the entire process goes as smooth as possible.

1. Would any type of coax cable work or do you recommend a certain rating? I expect the total cable run to be between 30-50 ft.
2. For now, I'm interested in only listening to lower frequencies (primarily airband), so would the UHF connector be fine? I've seen people talk about N connectors, but I believe its more to help with higher range.
3. My roof eave overhang is over 12 inches (photo attached below), can you please recommend a j-mount or another good option that'll work with this much of an overhang?
4. I live in Toronto, so we end up getting windy, icy, snowy weather, is there something I can do to weather-proof this setup?
5. I know it should be grounded, but I'm not too familiar with the setup, so I'm relying on my friend for that (he's a network installer, not much familiar with grounding outdoor antennas, but he's doing his own research)...is there something that we should definitely watch out for?
6. At the end,I believe I need to order the following parts: UHF connector (on the antenna end), a good coax, a BNC connector (to connect to the scanner), a j-mount (or something along these lines).

Many thanks in advance for your help. I apologize in advance if some of these questions sounds stupid, I'm just trying to take as many precautions and do as many right things as possible.