Hi, I have no experience with cnc at all, I own a hypertherm powermax 600

I would like to get a small cnc plasma machine, on a real tight budget, something only I will be using so great care will be taken with it, I can build the frame, I'm pretty good with building stuff although I have no knowledge of CNC the step motors or anything like that, so I'm not sure where to start to build my own

I have been looking for used machine and found one not far from here, but it is big 4*8 and a bit more than I can spend on it, particularly seeing how it needs some type of repairs which I would have no idea of what I am getting into on it, it is built by Built by Practical CNC, and they say it needs for someone that can finish some minor software program setup and redo the limit switches

anyhow I don;t mind starting out with a 2*2 machine, a 2*4 would be better of course so would a 4*4, if I were to get that 4*8 I would have to put it at my friends shop about 25 miles from me

anyhow I have need at this time to cut 3/8 steel, so I think the powermax 600 would do if cutting slow enough, I know I would like the 1000 eventually, (in fact that use done I mentioned had the powermax1000)
anyhow is there a decent small table I can partially build? where can I learn a bit more about building a machine instead of buying a complete package and will it save a ton on costs?
thanks I really have no idea about this

thanks for helping or pointing me in the right direction to learn a bit more so I can at least ask or search the right questions