In a perfect world (where freezer isn't an avalanche waitiing to happen), I'd use 1 quart freezer bags and freeze FLAT... then stack. Will thaw from rock solid in less than half an hour in luke-warm water. Since freezer space always seems to be nonexistent, I PRESSURE can in Mason jars.
I very RARELY toss any bones (especially chicken) without making some stock. Roasted a smallish chicken last weekend, tossed carcass into big pot, added carrots/celery/onions, topped off with water and just let it simmer away. Might only end up with a quart or 2, but pretty much FREE and very little work.
I'll do a big VAT-O stock a few times a year... usually beef and chicken. Definitely a COLD weather activity... usually during winter hibernation when bored or looking for an excuse to avoid housework!! Last time was when I found some great deals at the supermarket. One market SERIOUSLY marks down meat/poultry when it's 2-3 days BEFORE sell-by date... from $2 off to half price. Used 4 Cornish hens... seem to remember them not costing much more than $5 for all 4?!? Got at least 15 pints of stock. CH not a favorite... also ended up with a lot of meat that cat loved. Beef came from load-o bones and some big hunk roast.
Next time will try to be patient and cook WAY down... at least reduce by half. Will NOT add salt till very end.