Rhys got in before me with the clamping, I've just bought a decent cast iron drill vice (the last one was feeble), and a cross vice, neither of them expensive. I gave up on holding things by hand some years ago, after all dexterity matters to me, it's my livelyhood.
With hacksawing, as soon as you've got a groove cut then it's both hands on the saw, also cut in long strokes, using as much of the blade as possible. That's what I was taught in metalwork over 40 years ago.
Best advice I can give you is pick up a hammer before you buy, and choose one that feels good. I bought two repousse hammers off ebay, for class members to use when I taught enammeling (my hammer is sacrosanct). One is horrible to use, and the other is good enough to replace mine. One that's comfortable to use is more important than a particular brand, the days of dodgy cheap hammers are long gone thankfully.
You need two ball pein hammers, one light one about 4oz, and a heavier one 8oz, a repousse is handy for light metal forming.