A Pfaff 1245 from a private party would sell for $1500 to $2000 depending on age and condition and how it's set up. I would guess you could sell your machine, which is an older version of the 1245, for $1000 to $1500, again depending on condition and how the machine is set up. Specifically, what kind of table and motor the machine has. Prices can vary widely.
If you buy a machine from a dealer, it will cost a lot more because the machine should have been put in perfect working order. If you, as a private party, want to sell your machine, it will go for considerably less.
No one lives forever, the trick is creating something that will.