I select old style Elna, Bernina, Pfaff and Husqvarna Viking sewing machines. I replace old plastic broken gears with new. Ones and I totally service each machine including oiling, greasing, setting.
Particular fine example is PFAFF. The precision of PFAFF machines are amazing.
These machines are work force. I inspected and serviced every part carefully. It can sew 8 layers.
You can see the quality of sewing stitches I achieved using. These machines are one of best Pfaff made models. Everything in the pictures included. Carrying case is in great shape. The foot pedal plug has a chip but works perfectly fine.