Depending on what you want to do and are capable of, yourself, $5K can be pretty realistic.
As an example, there is (was?) a Tree Journeyman CNC mill with control issues, on the Vancouver craigslist for under $2k. From that basis, you have the options of learning the control innards, and fixing it, retrofitting or replacing the control, or converting to Mach or EMC (Mach is cheap, $150 or so, runs on Windows, EMC is Linux based, free, and quite a powerful tool, but with a steep learning curve)
A bud had a Shizoku mill (Japanese made, rock solid machine), bought off Ebay, converted and running Mach 3, making good parts. He was well under $10K tooled and producing.
A few months back (Can $ at par, time frame), I saw a Haas VF-1, mid 90's vintage, reasonable hours, 20 tool changer, 40 toolholders asst'd, on offer for $10K. Given the ease and cheapness of rebuilding a Haas machine, the cost of ownership on something like that is pretty reasonable, if you want a machine that can produce for you instead of just something that you can have sitting waiting for an odd job to come up. It was a running, ready to use, machine.
You gotta decide what you need for your purposes before you go shopping, though.
If you want to have the most flexibility, best ease of set-up, an open machine is probably your best bet. If you want to produce volume, and not have chips on the walls and ceiling, and enclosed machine may be better.
For one-of work, where the setup has to be knocked down and reset for each job, look at a decent manual machine. Helical milling is pretty easy. Set-up is the slow part. After that, its just crank the handles (or let the powerfeed do it). A universal table is nice to have, but really not a requirement until you start making things like your own drills and mill cutter blanks, where you need something closer to theoretical perfect profiles. Any Bridgeport style machine would be good for general stuff like that. Especially the decorative stuff like helical milling. Not rocket science, just time consuming and a bit fiddly to set up.
Universal dividing heads don't draw much money on Ebay, as they are a PITA to ship, but are still cheaper by far than buying one at a dealer, most of the time.
If you are looking for a machine that you can make a living with, producing large quantities of "stuff", spend the money appropriate your needs. If you want a machine that can do a bunch of different stuff, without a huge investment, those machines are around, and can be got cheap if you figure out what to look for, and you do a realistic assessment of need vs. want.
The "hobby" machines can make good parts, and the price of admission is low, but they are not in the same class as the commercial stuff.
Still, I think they would be worth assessing on their own merits. Worts case scenario (well, maybe not "worst" case, as in, it burns to the ground, worst case) is that you pick up a new hobby grade CNC machine, and learn a lot about set-up and operations from it, and then decide to sell it off for something more suitable for your needs later, or shunt it aside to put it to use for light work like engraving.
I deal a fair bit with both the hobby side, and work in a mostly manual machine shop full of good tools. I also run a faily old (early 90's) Milltronics open style mill, doing whatever we need to do on it, mostly programming with GibbsCam.
If you learn to use a lightweight machine to make parts, you will really appreciate the abilities of a heavy and rigid machine. You will make better parts, too, as you will have learned the value of good set-ups and proper tooling, IMO. Once you learn to make the machine do what you want it to, then you work on making it do it faster!
Checked out cnczone yet?
Cheers
Trev
