The siegs from Acer etc are quite simple to convert from experience spent one day on my X1 to get it up and running from scratch, now tidying and tuning everything. The X1 is only 250w but have already cut myself some steel T nuts with a carbide bit and some patience. Cost of my unit £580 for mill and £80 BOB and motors although had a few 3d printer parts laying around shop around and have a look if you can.