If you are thinking of buying a sewing machine for patchwork and quilting, here are some features that are particularly useful:
Speed control dial/slider– alter the maximum speed so that you can stitch with more control
Needle up/down button– you decide whether the needle is up or down in the fabric when the machine halts
Top loading bobbin– the drop in bobbin cases are generally easier to use than the side or front loading machines (with the exception of a Bernina!)
Needle threader– if you will be changing thread often this makes life easier!
Stitch length and width adjustment– so that you can make your stitches smaller or larger depending on the task
The ability to change the needle’s position– moving it incrementally to the right or left
Wide arm– for quilting buy the widest arm you can afford so that it will fit more comfortably through the machine at the quilting stage
Extension table– again for larger projects such as quilts or for appliqué this makes it easier as the fabrict has somewhere to rest whilst you stitch into it
Range of Feet– in particular a quarter inch foot for piecing; a darning foot, a walking foot; a zipper foot; and an open-toed appliqué foot. There are many other weird and wonderful attachments available but these are the most useful.
Thread cutter –not essential but if you are able to afford the option it does make life easier – particularly if you are manipulating large projects through your machine.
Spare bobbins– you need lots! Fill with the thread you use most often and then have a few spare that you partially fill with coloured threads for appliqué etc