I only sew on vintage machines. Modern ones have plastic gears and built in obsolescence. Why waste your money on that? (Unless you need the zig zag and fancy stitches and most of the old Singers -all attachments including zig zaggers and hemming feet, etc are cheap and everywhere).
These things were made in their millions and to such fine, exquisite engineering tolerances that they will still be here in another 100 years.
The other advantage of old machines (if you mainly like a straight stitch) is they do a perfect straight stitch - modern machines are less likely to. They are also designed to be maintained and fixed by the owner. Original manuals are easily available online - websites to ID and date your machine and loads of great YouTube videos to help with cleaning and maintaining. Most Singer manuals are free online and some even have repair manuals online.
My newest machine is 1970 (still metal, solid, well made) but the machines I use for everyday sewing are from the 1950s/60s. I have a Singer made in 1885 that sews a more immaculate straight stitch than any modern machine could. (That's all they were designed to do so nothing about it was compromised).
I have a 1917 Singer treadle in a cabinet in my living room and the cabinet holds all my cotton, scissors, etc - everything permanently to hand and well stored. Loads of info online about restoring cabinets as well as machines. And spares are available cheaply.
Can you tell I love vintage machines?