Base wager amounts for Probable Payoffs vary by track, using either $1 or $2, so it's important to note the displayed base wager when setting minimum Probable Payoffs.
Base wager amounts vary from track to track for the reported Probable Payoffs of Exacta, Daily Double, and Quinella wagers. Some tracks use a $1 base wager amount when reporting their Probable Payoffs and other tracks use a $2 base wager amount. For this reason, it is important to pay attention to the displayed base wager amount when defining your minimum Probable Payoff.