Makerbot charges $45 per KG for their raw material, whereas steel (in bulk) is more like $1/kg, and even in small orders (like say small bar stock) is $10-$15/kg.
That's why I wouldn't use it for anything else but prototyping. But what would you consider for fast prototyping instead of a 3D printer? With the same flexibility; you basically input (not that simple, but you know) a 3D model and get your prototype as output (like said; that's oversimplified but that's how I use it)?
But I am very new to this; it's only a hobby; i'm checking out 2nd hand CNC machines, but in my mind that's for the next step, after the prototyping.
Well, it depends on what you're doing. The problem with 3d printed stuff is that it isn't very strong - you can make crazy curved gears and stuff with it, but it's not going to hold load.
Honestly, for prototyping for small amounts of money, your best bet is probably a bridgeport-type vertical mill. You can do turning/lathe operations on one of those too with the right accessories. Not automated, and not fast, but if you need to make one off parts it's about your only option for hobbyist-type money. You'd be buying used, obviously, and you'd need a garage/workroom (This isn't something you set up in your house)...
There are some fairly economical small CNC machines now (We're talking $2k or so, price-wise), but they are intended primarily for model makers - any part over about 2"-3" and they literally can't cut it, where-as with a good manual milling machine and some time/sweat, you will typically have 24" x 24" x 10" travel available.
Makerbot charges $45 per KG for their raw material, whereas steel (in bulk) is more like $1/kg, and even in small orders (like say small bar stock) is $10-$15/kg.