I think that if you run across a project that requires a specialty foot, that is the time to buy it. You see the feet are quite pricy and buying them all at once could be a lot of waste unless you intend to use them. (IMO)
I love the #57 with the 1/4" seam guard, the walking foot, and the foot for making a covered seam (like jeans) I don't recall the number. I mostly use those but I have a couple others like the binding foot and the turned edge foot for scarves and baby blankets that I bought separately. Some people like a roller foot or Teflon foot for gliding over leather or nubby type fabric.
But, like I said before, I bought them as it became necessary.
I do some embroidery and did buy the thread spool holder. It is sitting in the box. I did not like it myself, but it could be useful if you have lots of thread changes and want to keep them in order of when they need to be used.
Last edited by RedGarnet222; 04-28-2020 at 08:48 AM.