It's always good to have a re-read!
I have had good luck selling on Facebook Market Place. You will, of course, get the usual dose of scammers, sometimes I play along, just to waste their time, and sometimes I dont - but they all come out of the woodwork within an hour of the ad going live. I have sold a couple of machines on there, the purchasers have come to collect/look at machine, and usually pay cash - there is no one taking a cut of your money like eBay!
https://www.facebook.com/groups/189544817106077 - this is a Bernina UK Sale or Swap group, might be worth joining (lots of useful info on there as well!). I had interest on my machine on there, and a lady is coming to see/buy on Sunday morning.
I have thought long and hard about the sale of mine, but as others have said, I will have the money rather than having it sitting there doing nothing whilst I prefer to use the other machine!
Good luck with however you choose to sell!