Bahco Laplander is highly respected as the one to carry. They cost about thirty bucks. The saw I have is a ten dollar saw and it cuts like a ten dollar saw. The blade is flimsey and ad to that a poor factory grind on the teeth, I am waiting for the blade to bind up and break. The folding saw is a tool to not be cheap on. At the end of the day, a better quality saw will have saved you calories.
Also small finger sized mini saws are priced friendly at a few bucks, and very handy especially for primitive traps. My Swiss army knife has a small saw blade. At one time I scoffed at its diminutive presence until I actually started applying it for tasks it was designed for, in which case does not include cutting large stock. The #7 Notch is instrumental in primitive traps and general camp set up, and those little mini blades work best.
A person is looking to save calories, time and risk of injury, but the saving of money is likely to diminish the affect-ability of these three primary priorities.