I downscaled to a second hand cast iron singer from ebay recently and gave away my newer machine, no regrets!

No fancy stitches on these older machine, so to zigzag or buttonhole, you need a separate attachment, but they'll do most perfect even straight stitches ever. Parts, even new motors, are still widely available for the most common models and there's lots of info on the web. They're very heavy to ship, so getting a bargain is most likely if you find one to pick up near you.

If you look on ebay or decide to research them, the main ones to look at are:

singer 99: excellent smaller cast iron

singer 201: very large and heavy, can sew leather, engine as smooth as a rolls royce, and said to have been used to sew rr upholstery, not that I would know--the people who serviced it for me said it ran nicer than anything they'd seen. It's a real monster to put away and get out.

singer 221 or 222 -portable and free arm portable, favourites of quilters and a virtual cult in the US, so unfortunately very pricey there, 222 also have a free-darning attachment.