I have a 2015 Frontier SE and the prodigy brake controller was easily mounted with an adapter my trailer guy sold me. I let him do the drilling and mount it because he offered and I was there. But it would have been pretty easy to do myself. There was no brake controller included with the tow package for my truck, at least.
As for the stinger, I got one with a 4 inch drop for my 13 foot Scamp
says you need an 18" height with your ball mount. That's what got me there. With that, I am dead level without the bed or Scamp
filled up all the way. But with a Casita
with higher tongue weight
, things will be different for you, so best to try to wait and borrow one until you figure it out, like others have said. If you are "pretty close" to level, but a little high, you can probably tow it home a few miles from your friends' house if it's not highway driving. You don't want to tow it if it is too low though.
Sounds like things are coming together. Good luck!