This is gold, every once and a while I share something profound. You earned a nugget making me laugh....
During the growing phase of any deciduous tree, the canopy and trunk must always remain 360. No part of the trunk can die, and no part of the canopy can die or get weak. To work on either part of those two places on a tree, requires both to be healthy and 360. No roots below, can't grow branches there. No branches above, can't improve the base.
This is just a fact.
When the tree is finished (you know what I mean) one or the other can change and the tree will not be compromised. Most of the time it will stay in it's present form. Just know that it can't be improved because something changed in the shared 360 so you have what you have.
If you buy a tree with a lot of trunk damage like a whole side, you can never really improve the base because there is nothing above to really deal with that. Just remember that the foliage above may look 360, but the canopy compartmentalised itself off from the dead portion. If you don't do anything stupid you can keep it the way it is. If you prune the canopy hard on the dead side of the trunk it will slowly wither and die away over a year or two.
Same with the bottom, grafting roots on the dead side just will not work. Its been compartmentalized off from the rest of the tree to survive.
That's why this tree is not good for bonsai, and probably the reason someone is willing to part with it. If it were that good why not take it to the next level themselves? So the guy puts in on the net and people are willing to buy it, at a stupid price to boot, with the thought of saving it and making something out of it. Thats why I said this thread gives the "Art" a black eye. People don't have any idea how plants grow and how they can be improved. They just buy it cause it looks cool, not knowing that the great things they might have learned here over the years will not work on a tree like this. This is a very artistic thing we do with plants. A person with knowledge knows this and that why sometimes you all don't understand why some of us old timers say harsh things that many of you youngsters don't agree with. I only say it the same way your Dad should have.....tough love.