Friend of mine runs a small business making noticeboards and suchlike, and wanted to be able to engrave writing and logos in-house. He bought a 6090 size machine from Acctek a couple of years ago for about £3K, including shipping. It's a bit rough round the edges and needed a day or two to set up but has been running pretty well for his needs. He spent quite a lot of time talking to them via Skype to agree the detailed spec. I doubt if you could buy a new ready-to-run machine for much less, at least one that will stand up to light commercial use. There is always a bit of uncertainty in buying from China but it all worked ok in this case. As already mentioned, there are other possible lower-risk and maybe better quality machines available - but at a price.