I bought my first featherweight - 221K - from a charity shop where I used to get the machines donated to them working and clean and ready to go. A local charity where I used to live, nice couple ran a shop from premises they owned themselves, we are friends with them still. Worked on more machines than I can count, sold some of them on ebay for them - they are older and not techy at all
I paid them £50 for it - they wouldn't take any more.
They are the folks - well the wife - who gave me the 66K back clamper with green lotus design - it had been her machine long ago and thought I would appreciate it. I do, and I recently bought a set of back clamping feet to replace those that were lost.
They also gave me "Lyra"
I replaced the motor on her German Singer a few years ago - I think I wrote on the old sewing forum about it?
Second 221K - local charity shop here - had £10 on it because it's electrics were incomplete and it wasn't possible to say if it would even work.
This one today - 222K £45 in a somerset shop - they had three machines in store, this was the cheapest! maybe because it was small, or because the case was so dreadful(not sure if the case is saveable)
I guess I must go to a lot o charity shops, now I start writing it down