Just some thoughts on the 'really expensive machines' in shops. Granted, the $500 mentioned for an SU is way out of line, and certainly someone like Miriam knows what she's looking at at and what things are and are not worth. Also, caveat, I am the first in line to want a good deal, and generally one to scorn Fad-Mania pricing, honestly!
However, the one thing I do want to say is that there can be a big difference between a $40 Craigslist machine and the "same" machine from your OSMG with triple the price tag. While one's instinct is to balk at the expensive Shop Tag, in an ideal world, the one in a shop has been tended to and brought up to snuff by Real Person Labour, and also comes with some sort of trust, standing behind it, etc. There is something very valid to be said for keeping local people in a job. It's good for everyone. (As I said, ideal world... I know there are sheisters out there, having recently paid too much for something myself from a local shop and in the end having been royally hosed. And it really stinks when there are trolls out there masquerading as nice shop owners. Grumble.)
Here, we tend to be tinkerers. So we are happy to get a $25 machine and tinker away for HOURS to get it up to snuff, because it is our hobby. However, if you took that same machine to someone to have cleaned, de-linted, baptized in Tri Flo and annointed with SM oil, polished, etc etc etc, you can bet that the labour there would cost a pretty penny. A good example of this is my $20 Pfeffer 130 knock-off. I spent -hours- cleaning, re-wiring, etc etc... And it easy to balk at the "same machine" with a $200 price tag, but if that same machine has been given the Royal Treatment, that may be a different story.
Anyhow, it's all very interesting to me, this whole concept of "worth" as applied to these wonderful old machines. I see a lot of confusion and mania over the intrinsic value of machines, the "List Price", the "going-for-on-eBay" price... I think sometimes we tend to be guilty in both directions, under-valuing one thing, over-valuing another. I'd love to know what others here think as well!
(And I will also be the first to admit that I will be vulnerable to non-sensible thinking when I finally land my eyes on a RLPSM*.
I also broke my fifty-cents-per-pound rule when I bought my Featherweight.)
-Cecilia
RLPSM = Real Live Pink Sewing Machine