MILL VALLEY, Calif. (KGO) -- Rummaging through boxes of old family heirlooms, you might find something that seems valuable. A piece of silver, an old document, an autographed photo? How do you know if you've struck gold?
Cathi Sullivan of Mill Valley ran across something among her family heirlooms that made her gasp with excitement. It was a letter to her father from Walt Disney himself, his signature at the bottom.
"It was so exciting I think oh my God, wow," said Sullivan.
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Her father, Mark Sullivan, was a carpenter who helped build Disneyland. He was on the crew that created Adventureland. Disney sent him the letter when the park was nearly completed, inviting him and his whole family to the opening in 1955.
"He wanted to thank everyone for their hard work and say how much he appreciated it,'' Sullivan told ABC7 News.
The family did go to the opening when Sullivan was only 8 years old. She, said at the time, no one in the family realized the importance of that opening, nor how famous the park would become.
She recalls seeing Minnie and Mickey Mouse and recalls being impressed by the size of Sleeping Beauty's castle.
"There was a little parade and Walt Disney went by and waved at everybody,'' Sullivan recalled.
Otherwise, she rarely thought about her father's role in building the iconic park until the letter turned up. She also found her father's employee identification card showing he worked at Disneyland.
"I wondered how much value this might have,'' she recalled. "It's certainly a part of history."
The letter praised the workers for trying to finish the park before the premiere was to show on television that summer.
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"As we come to the homestretch in the building of Disneyland, I know you are as happy as I am with the way in which this dream of ours is coming to full life,'' Disney wrote. "I would like to cordially invite you and your family to participate with us in the thrill of the Disneyland premiere."
"It was really sweet,'' Sullivan added. "It was the most giving thing that anybody did because times were not easy."
Though the letter was typed, she thought for sure the signature was handwritten, something collectors treasure. But she could not find out how to authenticate it or how much it was worth. She contacted 7 On Your Side and we connected her with an expert in historical documents, Sandra Palomino of Heritage Auctions in New York.
"It's certainly an interesting letter representing a significant event in history,'' Palomino said.
But the signature? It was not by Disney's hand.
"It's not a real signature, it's a printed signature and usually in those instances, it wouldn't really have much value,'' Palomino said.
Not only that, the letter itself was a form letter, she said, with Mr. Sullivan's name inserted on the top.
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"You can tell because the typeset of the name compared to the type of the body of the letter, it's slightly different,'' Palomino said.
Sure enough, as you can see in the video, the two typefaces are quite different.
Still, Palomino offered some hope. She said it was Mr. Sullivan's employee ID card that gave the items more value.
"If you combine the letter with the employee ID card, that will be of more interest to collectors,'' Palomino said. "This was your dad, so it's coming straight from the source. So you have this letter saying hey thank you for all the work you did in contributing to the building of Disneyland, and the fact you can pair that with his actual working identification, that's where collector interest is going to be."
To find out what an item is worth Palomino says go online and find out what similar items sold for on auction sites, including eBay, then put your item out to bid. It's wise to have an idea of value before you sell, so you have a better chance of getting the most for the item.
Her guess as to the value of Sullivan's letter -- $500 - $600 with the identification card.
Sullivan admits she was disappointed it wasn't the life-changing discovery she had imagined.
"The bottom line is it's not worth nearly what I hoped,'' she said. "But oh, I'll hold the tears."
Click here for more stories, photos, and video from Michael Finney and 7 on Your Side.
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