Power and money (and medicine).
Just look at his wife,
Again, the guy is loaded. When he kicks the bucket, the loot is hers. He's known as a "SugarDaddy." She only has to put up with him a little while longer (EW!). This campaign will be her dream come true, because Trump will push his abused and aged body a little too far this time.
>> When he kicks the bucket, the loot is hers <<
I don’t think we can reach that conclusion unless we’re privy to the pre-nup between Donnie and Melanija. She will certainly get a bundle, but probably nowhere near the 50% that (by law in many states) normally goes to a widow. I imagine the lion’s share will go to his kids and grandkids.