Gilbert had a winning weekend in Las Vegas in early December, but he came upon some really big money at the airport as he was about to catch a flight home.
Gilbert found $10,000 in two unmarked Caesar's Palace envelopes.
"There was $5,000 in each envelope. I just about fell over, I couldn't believe it," Gilbert said.
He discovered the cash when he opened the envelopes at his home in Greenwood Village.
"If it happened to me I sure would want that back," Gilbert said.
Some may have thought they hit the jackpot, but Gilbert knew he had to return the money.
"I wanted to show my kids the right thing to do. It would have been a lot easier keeping it to be honest with you. But I felt like I had to get it back to the right person," Gilbert said.
He called the airport in Las Vegas, but they would not even take down his name.
"They didn't do that. It was against the rules. I just said, 'Well, I'll keep calling back and I'll give it 30 days,'" Gilbert said.
Gilbert kept his word to continue calling the airport. More than two weeks later, the operator told him a man in El Paso, Texas reported losing two Caesar's Palace envelopes full of cash.
"She goes, 'Well, this is breaking the rules, but you're trying to do the right thing,'" Gilbert said.
9NEWS reached Ignacio Marquez by telephone from his home in El Paso. Marquez says he won the money gambling and dropped it as he was running to catch a flight.
"Relief is an understatement. Cash money is very difficult to get back. I'm very appreciative to Mitch and his family. You do not find people like this," Marquez said.
Marquez knew the odds of someone actually returning $10,000 were pretty slim.
"I will always thank Mitch for doing this. That could have easily just gone south, instead of what happened," Marquez said.
Gilbert deposited the money in Marquez's bank account just two days before Christmas.
"I think he was pretty much in shock. I don't know if he believed it," Gilbert said.
Even though Gilbert's real estate business is slow, he says returning the money was the only option.
"I would have loved to have $10,000. You think about all the bills you can pay. But it didn't belong to me," Gilbert said. "It felt so good to be able to get it back to the guy. I felt like I was floating on air. I felt like a million bucks."
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