Advice for buying a K40

[NickWL]

The K40, once DSP upgraded (no small task - straightforward but not trivial) is a 'real' machine. I'm cutting A4 ply and Perspex up to about 6mm, engraving the same and am now exploring the other end (paper and cardboard).
It took a fair bit of getting to and a number of cock-ups (mainly of my own making) but the end result was worth it.
Would I do it this way again? Probably not, but I'm very glad I did it the once since I learned an awful lot along the way!

[NickWL]

It's not difficult if you're used to wiring - a little bit of improvisation here and there helps.
I didn't count the hours, I suppose half a day to strip out and modify the housing (if in doubt, double the size of EVERY hole in the machine and line the edges with grommets!
Installing the hardware was fairly quick, wiring up I did over about four sessions to the point where it was 'working'.
Fine tuning, troubleshooting and the like mostly involved waiting for parts to come from the States: 3 ammeters and a spare constant-voltage controller to power them was my main 'wait'.
Marco at Lightobject is very helpful (though he doesn't suffer fools gladly) - most of the answers are in these [rather disorganised] posts somewhere.
A tiny bit of common sense when interpreting the wiring diagrams can be helpful too.
Hope this helps! Go for it!