Vintage accordion

For sale ! Vintage Accordion Paolo Soprani madame 3! ( Was my dad's ) $695.00! For repair! Looks great ! With yellow case ! Only issue is when I play it I Get double notes on certain registers and certain octaves! Apart from that all is ok! I have no idea on how to repair ! Great project for an accordion person ! In working order they sell for over $1700.00! Please contact me thank you!