What do want to sew? I see that you have chosen all horizontal bobbin machines and was curious as to why. Those are all good straight stitch machines. The 66 & 201 are full size machines, whereas the 99 is what is considered 3/4 sized.
1. The ones with belts are fine for a beginner.
2. I don't know why there isn't a number after the dash, other than that the basic tag could be made and then depending on whether the customer wanted to have the so-called sub model as to whether it was a hand crank, treadle or belted motor. The 201-2 is the machine with a potted motor. There were 201s that could be treadled, hand cranked or had a belted motor.
3. I'm not sure, but I would suggest a surge protector - After checking the condition of the cord and replacing if necessary. Some will rewire no matter what.
4. No not all machines can be used without a base, as it will interfere with under workings of the machine. Depending on what you want to sew, a cabinet or table would be preferred. A base or case will sit up above the surface it is on and sometimes have a tendency to scoot ( or at least the modern machines do). Also a flat surface that is even with the bed is preferred to minimize the drag on the fabric through the machine.
I see Leon has posted, before I finished. I agree with him.
Janey - Neat people never make the exciting discoveries I do.
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