I am sometimes asked if you need a serger to sew clothes. Specifically knit clothes. Knits are the stretchy fabrics that can give you a harder time if you don't know how to use them.
I love using my overlock/serger for sewing with knits. I love that it cuts the edge for me, making it completely clean, without any excess seam allowances. I really appreciate using it when I'm sewing over bulky fabrics that my sewing machine would 'cry' about. I like that it doesn't stretch my knits unless I want it to (there's settings for that). There are so many options available on amazon.
It takes a learning curve to use a serger though, and there might be a few garments that are ruined in the process. You can't tear out overlock stitches, and the cutter, while wonderful, is also your enemy if you turn your fabric incorrectly. The other thing that is entirely terrible about an overlock machine, is the threading. There are times when I feel like I waist an hour, simply fiddling with the thread or tension.
To answer the question, "do I need a serger to sew clothes?", the answer is absolutely not. Any of my patterns that you CAN use a serger with, you can also use a regular sewing machine. The trick is the stitches that you use. A serger's stitches will have give or stretch to it. Which is perfect for knits. However, a straight stitch on a sewing machine will not stretch at all. This is easily fixed by simply switching the setting on your standard sewing machine to a zig-zag stitch or elastic stitch. Both of which will have plenty of give/stretch for a knit fabric.
I also notice that whenever I sew a knit fabric with a standard sewing machine, I get puckers. These are normal and easily fixed. Simply press your fabric with a hot iron, or as hot as the fabric will allow. This seems to allow the fabric and thread to shrink back/stretch to the new dimensions that you gave it by sewing. It works like a charm almost every time.