Hey, John -- thanks very much. I shop CL and thrift stores, Goodwill, Value Village, etc. I sometimes wonder why more people don't value these machines but then I'm thankful they don't because that means there are more for us. There are lots of inexpensive, great machines out there but sometimes they take some digging.
The Singer is the $9.99 machine, a thrift shop buy. After getting it home, I tested it by doing some sewing (no oil, right out of the case). It stitches well and is quiet. The feed dogs feed evenly, so the material remained straight while sewing. Then I opened it up full throttle at the widest zig-zag and broke the needle. It's in great shape -- nary a ding nor scratch on it. I looked for plastic innards and couldn't find any and it's fairly hefty, although the top and nose plate are plastic as is the presser foot pressure control knob and the clutch, although the hand wheel is metal. It's made in Monza, Italy. It seems to be a good machine overall. Basic, sturdy, but lighter duty than a Kennie.
The other three were CL finds and cheap!