CNC's are perfect for inlay. I'm trying to use mine to do as much as possible as I struggle to learn Fusion 360, but inlay can be accomplished with Vcarve, a much simpler program. I did some corian inlays of sycamore leaves on a uke fretboard that turned out pretty well. I'll try to find some photos. There is a method of inlay called "vcarve inlay" where the male and female parts are cut with a v-bit rather than a straight bit. This has the advantage of better fit - especially when it comes to fine details. Search youtube for "vcarve inlay technique".
As far as the machine is concerned, I agree with everything Sandy said. I bought a 4'x4' CNC direct from China from Omni. There is some legwork involved as you need to hire a freight forwarder to help you with getting it to your door from China, but it's not a big deal. Also expect much less support from the manufacturer, but I spent about $6000 CAD for an industrial strength CNC with a welded steel frame, liquid=cooled spindle, 1200mm x 1200mm cutting capacity, and a rotating 4th axis. You just can't get anything like that for that price made in N. America. Plus a lot of the "American made" CNC's consist of a steel frame welded in the US with Chinese spindles, ball-screws, steppers, controls, etc. The frame is the cheapest part. What you're paying for is support. Alright I'm off my soapbox. Just my opinion and experience.
For software, For inlays, Vectric Vcarve is all you would need. It was around $700 USD when I bought it. You do not need their flagship program, Aspire, which is twice the price for the additional functionality of 3D.
For all design and 3D work (carved top guitars, necks, violin plates, etc) I use Fusion 360. It is a full CAD/CAM solution and does a much better job with CAD design than Vectric software. Plus you can get a free license if you are a startup business making less than $100,000 per year. Not difficult to fall within that parameter doing luthiery! Why not just skip Vcarve altogether and just use Fusion? The learning curve on Fusion 360 can be steep if you do not have much prior CAD/CAM experience, and Vcarve does vcarve inlays really well. The name of the software says it all. It's also really good for quick 2D stuff like cutting out a soundboard and cutting the rosette channel, making jigs, etc.
On the attached photos, the fretboard is bartlet pear. I originally tried making the male inlay pieces from padauk but found it too chippy to hold detail so I grabbed a piece of scrap corian from an install job I did. It was the piece left from a hole saw. Corian is hard to come by here so I take what I can get.
[/img] This was my first attempt at inlay with the CNC. It's not perfect but a hell of a lot better than I could ever do by hand!