Is there any proof that Donald Trump ever voted (before voting for himself)?

Trump on Facebook, 13 August 2016, promising to
change system from "Rigged" to "Fixed."

It was strange when Ivanka and Eric Trump couldn't figure out the rules for voting as Republicans in this spring's New York primary (I figured out how to switch from "No Party" to "Democratic" even without my father running), but maybe voting has never been a high priority within the Trump family before 2016.

This feeling was reinforced when Donald Trump said the following to Bill O'Reilly as he started his latest free-fall in the polls:

“The whole thing with voter ID identification I think is really — I mean people are going to walk in, they are going to vote 10 times maybe. Who knows? They are going to vote 10 times. I am very concerned and I hope the Republicans are going to be very watchful and I hope the authorities are going to be very watchful.” --Trump on Fox News, August 2

Who knows? Anyone who has ever been at an actual local polling station knows that this sort of casual "going to vote 10 times maybe" would be impossible. I've only voted in five different places in two states (New York and New Jersey). None of them ever required photo IDs, but once you signed your name in the book, there would be no way to sign twice (or ten times) without having created multiple identities at multiple addresses in advance. How could a significant number of people be recruited to commit these crimes?

By this week in Pennsylvania, Donald Trump was keeping the same conspiracy theories alive, though now admitting that the thousands or millions of vote fraudsters might only be voting half as many times:

"We're gonna watch Pennsylvania. Go down to certain areas and watch and study and make sure other people don't come in and vote five times. ... The only way we can lose, in my opinion -- and I really mean this, Pennsylvania -- is if cheating goes on. I really believe it." --Trump in Altoona, Pennsylvania, August 12

Trump is currently down by more than 9 points in the latest Keystone State polls, and he has never led there, but if he loses in November it will only be due to "those people" voting 5 or 10 times? This is dangerous anti-democratic and anti-American demagoguery aimed at the most credulous elements of his uneducated base of supporters, and it will be amplified by the Republican spokespeople of Fox News who still harbor fictions about Romney losing Pennsylvania because of fraud.

Now, even though every polling place already has official poll watchers from both parties at every local site (something that most 70-year-olds with a lifetime of voting behind them would probably know), Donald J. Trump is asking supporters on his website today to volunteer as "Trump Election Observers" to "Help Me Stop Crooked Hillary From Rigging This Election!"

As seen on donaldjtrump.com on August 13, 2016.

There has never been more of a need for an absolute landslide for Hillary Clinton. Every vote in every state counts in 2016. A decisive electoral college victory will not be enough to convince the most hardcore conspiracy theorists, but a popular vote burial of trumpism will insure that the conspiracy theorists might remain a very small nutcase fringe rather than a main current of Republican thought.

And are we ever going to see any documentary proof that Donald Trump visited an actual polling place before he voted for himself in 2016?
(UPDATE 10/21/16: Click to see video of DJT and Billy Bush voting in 2004.)