What are JANOME 140M sewing machines like?
I believe you answered your own question. What good is a machine that will only sew together to layers of thin cotton? Take the money you were going spend on this machine and visit sewing shops to see what they can do for you. Tell them you have a limited budget or they will start by showing you the Rolls! Tell them what kind of sewing you want to do. A good sewing machine should be able to sew fabrics ranging from nylon to canvas. You want a machine that has a buttonhole feature and sews a nice even straight stitch. Ask to test what they offer. A used machine may be a good machine to start with.