$6.50 for rats is nothing. Back in 79-80, I got $7-$8 for rats, $40 for coon, $70-$80 for fox, and on and on.
I had been making $3.85 an hour at Winnebago before I quit to trap full time. A new Ford 3/4-ton 4x4 pickup was $9995. About as much as guy could make trapping your arse off for the month of November. DIdn't get much sleep back then. I kept telling my wife I could sleep all summer!
I made a darn good living trapping back in the day... up until '87 when Black Monday hit and the bottom fell out. The competiton and thievery was unbeleiveable though. You don't want that again.