When I was training for cycling events I got tired of paying an obscene amount of money for "top quality" sports drink. I did some calculations and found out I could approximate Gatorade very closely by using powdered lemonade with about 1/8 tsp of "Lite Salt" and a pinch of regular salt in each bottle. (Lite Salt is a reduced sodium table salt that contains potassium chloride).
I now get several months' worth of Country Time in the giant canister from the restaurant supply depot for about the same price as maybe one week's worth of powdered "sports drink" mix. The can of Lite Salt I bought a year ago is still mostly full.
Cheaper still is to just use water, sugar, salts, and a squeeze of citrus or something else for flavor and/or acidity. I did that for a while too but the cost of bulk lemonade mix is pretty low and the convenience factor is worth something to me. Plus, I never seem to tire of the taste of lemonade when I'm sweating buckets. YMMV.
Now don't get me wrong, there have been bona fide advancements in sports nutrition in recent decades, and not all sports drinks are equal. Professionals and other elite athletes can see serious benefits by using the latest high-tech nutritionals. But for most moderately athletic activities where you are sweating buckets and tiring out your muscles, you mostly need water, sugar, and electrolytes during long workouts, along with ordinary healthful foods in your diet. No need to pay $1 or more per workout to stay hydrated!