Trump is not "self-funding". He is using donations and proceeds from the sale of campaign merchandise to pay for part of his campaign expenses, and he has "loaned" his campaign money for most of the other expenses. Of course, he expects to be paid back for his "loans" with interest from future donations. So the best you can say is that he is fronting his campaign the money that he expects to receive later. But that is not the same as "self-funding". If he were truly self-funding, he would not accept donations, and the money he is fronting his campaign would be donations from him, not loans.
Oh, and who is most of the money that the campaign is spending going to? Why right back to Donald and his companies! His campaign is renting office space from his own companies (at a hefty rate, I am sure). So win or lose, Trump's company stands to make money from his supporters.
They might even be able to get Goldman Sachs to loan them the money.
Oh they can't because they do not have the funding in a bank account or assets with their name on them. Hmm but Donald does have the funding. And he is giving that funding to himself.
Pay the games you want but we can look stuff up on Federal Electional commission database too - as far as American presidential politics go Donald Trump is self funding.
Now you touch on an advantage he has that I mentioned from the very outset of his campaign when he was poo pooped pretty much everywhere. Physical assets and vast human resources. Luxurious little safe houses all around the country, a heavy jet, nice chopper and he has a staff of around 20,000 people.
I like advantages I also like job creators - makers not takers.
What have any of the other candidates actually made?