Welcome! I am not the one to answer your questions, but I thought I would mention the stacking cubes that are sturdy and offer a variety of levels for leveling. My husband had taken care of that part, I just set it up while he backs onto them.
One thing I can remind you--do back onto the levelers. That way, when you move out, you are going forward and don't have to watch all the obstacles that might be in the rear. One of our neighbors lost an awning because someone was backing off of leveling blocks...and missed the rv, but not the awning.
Also, you might think about something long enough and wide enough to support both tires on a side. I understand there is less stress on a tire that way.
Again, welcome to the forums and I'm sure there will be lots of helpful hints!