WoG...First I will say sorry for us hard headed folks for hijacking your thread.
Sunken, The point behind of all of our banter is to try and help you and others that may come along well after your project is complete.
So here is my perspective from a guy thats only been doing upholstery a few years....
I started on this:
1953 Morse 4300 zig zag... It was not a walking foot, it was not a industrial strength... What it was, was an all metal, well made machine. I did almost me entire boat with this. It worked fantastically. (for what I knew at the time)
Then my friend WoG, hooked me up with as well: A 1948 Singer 15-91
The combination of them both finished my boat... It also started giving me perspective...(What was good and bad from each) Both of them together was like the dynamic duo!!
Then I started to learn about walking foot machines.... and what I learned is many of the issues I didnt care for with the straight stitch machines, were solved with the walking foot...So I went on the hunt for one of them. I ended up with a Juki 562
I think the point I?m trying to make is that no matter what machine you get, you can get the job done, some machines will make the job easier, but not exactly absolutely necessary. Depends on what you want to do with the skills/tools after your project....
Now back to our regularly scheduled program?