Beethoven's 5th (2003) on Netflix

Plot summary

The old mining town of Quicksilver is where Sara Newton and Beethoven spend the summer, at the home of Sara's maternal uncle, the clumsy mechanic Freddy Kablinski. The Selig fortune has been a local legend there for years, and nobody has found a trace of it. Then Beethoven digs up a clue to where the two bank robbers, Moe Selig and Rita Selig, are said to have hidden their money. Word of the find spreads quickly, and a treasure hunt takes over the community, with almost everyone hoping to win the dog's attention. Freddy and a boy named Garrett join Sara in trying to uncover what Quicksilver has kept hidden for years.