When I had children still in my home, I bought 4 lugs of peaches for preserving each year. That seemed to meet our needs nicely.
A lug weighs about 15-17 pounds. The number labeling their size (for example, 50) means that there are 50 peaches in the lug. Smaller peaches labeled 56 would be a smaller peach and 56 of them fit in the lug. I generally buy the 50s.
The Faye-Elberta variety is my favorite. Besides being a delicious peach, the stone comes out easily and the peel comes off nicely when scalded.
Equipment to keep on hand includes a water-bath canner, a funnel for filling the jars, mason jars with lids and screw bands and a jar lifter (a clamp that is especially made to lift the jars from the boiling water-bath.) Ingredients needed are peaches, sugar, water and ascorbic acid crystals. I use a product called Fruit Fresh for ascorbic acid.
I also like to make peach pie-filling to keep in my freezer. It takes Minute tapioca, sugar, peaches, lemon juice, ascorbic acid and salt. I freeze the filling in freezer bags. In the winter I put the frozen filling in a pie pastry and we enjoy the summer’s fruit at short notice.
If you get the chance to try the canning process, the Ball Blue Book has many good recipes to try. Several of them use peaches. I recommend this annual event highly.