What you say is true of milling machines and lathes. Small light machines are expensive compared to larger better quality machines. The downside of the school machines is they can only make small parts. There are some small industrial machines but as you say few and far between. Have a look on Gumtree and machinery auctions/ dealers. The electrical retrofit gear from China is as cheap as chips but read through the forum at other peoples posts to find out what is good.