USPI coins are on fire lately prices have been quadrupling in the last year or two. The pesos in particular have been jumping in price. The United States pesos from 1903-1912 is a challenging set to complete in high grades. Do you own any pesos in your collection? I have them all except the 1906s. I am also missing the 1905 and 1906 proofs. The photo below isn’t mine but in case you aren’t familiar with the series, see the coins below!