As Laurence mentioned, starting with files might be the easiest and fastest way for a hobbyist to dip their toes in the water and get a few knives under their belt. That's how I started too, and I don't regret it one bit.
You don't even have to build a HT forge/furnace, necessarily. You can just temper back good files in your kitchen oven at 350-400F for an hour to bring them back around 58Rc for toughness, grind 'em down to a cutting edge, and frankly have a pretty decent knife. You're gonna need solid carbide drills if you want to make holes in the tang to accept pins or bolts, to hold handle scales onto it. Or you could just cord-wrap the tang and still have a good, handy, comfortable knife.
I recommend staying away form the HF stuff and spending $150 or so on a Craftsman 2x42 and putting a tempered-glass or hardened-steel platen face on it. It's a decent little machine, and there are a wide variety of high-quality belts available in that size. If you find you're using it a lot, you can easily convert it to run 2x72 belts. (for even more variety and efficiency)
Some people earn a decent living making nothing but file knives.
Is a file knife gonna be the bestest knife ever?
No. But does it have the potential to be a dang good knife that performs better than the factory-made stuff on the shelf at Walmart?
Heck yeah!
And you don't have to re-finance your house to make it happen.
