Finish Seam without Serger the Great Debate?

My wife is a seamstress who used to make and sell kids clothes. She makes all my summer shirts and shorts and makes bulet proof vest covers (I'm a retired cop). She says she hates to agree with your wife but the Serger is the way to go. It can be done without one but the time savings are enormous and if you are going to sell stuff there is no way to get the same results. The edges and seams are markedly more professional with a serger. My wife says go buy it! She said you don't have in invest in an expensive Viking or other brand but once you use one you'll wonder how you got by without it.