I used a Greist #1 buttonholer with my Singer to make the buttonholes. This Greist is a straight-stitch model. It makes wonderful buttonholes.
Just to name a few:
It fits me, with no alterations.
There is no hand sewing.
It can be made with a collar stand or a notched collar.
The instructions are easy to follow.
There are a minimum of pieces to sew together.
I like the style.
I paid .30 for it at the thrift store.
Thanks for stopping.