The story has been confirmed by Jake Turx here who spoke to both and Eric and Donald Trump Jr.
In 1995 Donald Trump was traveling along a New Jersey highway when the limo in which he was traveling experienced a flat tire. Spotting the disabled car along the side of the road, a passing motorist stopped to offer his assistance. After helping, Trump asked how he could repay the good samaritan. The man asked that Trump send his wife a bouquet of flowers. Trump agreed. True to his word, the bouquet arrived several weeks later along with a note saying, "we've paid off your mortgage." They were an Orthodox Jewish couple from Lakewood.
In 1995 Donald Trump was traveling along a New Jersey highway when the limo in which he was traveling experienced a flat tire. Spotting the disabled car along the side of the road, a passing motorist stopped to offer his assistance. After helping, Trump asked how he could repay the good samaritan. The man asked that Trump send his wife a bouquet of flowers. Trump agreed. True to his word, the bouquet arrived several weeks later along with a note saying, "we've paid off your mortgage." They were an Orthodox Jewish couple from Lakewood.