1. Brakes are easy to adjust, just take a bit of time. Jack up the axle and block it, remove the dust cap from the adjusting slot, with either a flat screwdriver (or better yet an offset brake adjusting tool) spin the adjusting star wheel until the brakes lock and the wheel is real hard to turn, then back off on the adjustment until only a very slight drag is felt. Repeat for every wheel.
Plan B - take it to a shop.
2. I don't check quite that often, but do check a couple times a year. I usually shoot for 90-100 ft-lbs.
3. What I do is 'pull the pin' while hooked up, and then try to pull the trailer and see if in fact the brakes are locked. I use a wee bit of white grease. Never cleaned the contacts though, but a buff with a bit of Scotch-brite should work fine.
4. A degree or two off level won't hurt and RV fridge, and traveling is fine with it on too as it jostles the liquids about.
5. I have a small container of hitch lubricant, which looks like a white grease. I have use axle grease in the past with great success. You want to use a fairly thick type grease, and only need a thin film of it. I regularly wipe off the ball and the inside of the hitch and reapply a bit to just the ball. I would not use a solvent based lubricant. I think this is one of the most neglected maintenance items that can have dire consequence because of poor maintenance. It probably costs me about a minute tops every once in a while to do, and keep the connection between vehicles working good.
You will likely have much more sage advise added. I have only told things from my limited knowledge on your queries.
2017 Escape 5.0 TA (someday soon, I hope
2015 Ford F150 Lariat 3.5L EcoBoost
2009 Escape 19 (previous)
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