I bought a used Shapeoko XXL a little over a year ago. I love it. I have upgraded the Z axis to the HDZ (Ball Screw) and added the touch probe and the bit setter.It's a very lightweight hobby machine. Be aware that as the size increases, the rigidity will decrease rapidly. Meaning the smallest version will be much better than the largest version.
With CNC machines, you get what you pay for. If you buy the cheapest machine you can find, you'll likely be getting the lowest quality machine.
Carbide3d makes these machines and has CAD/CAM programs that are free. The Carbide Create (CAD) has a pro option that is currently free if you join the community forum. You can do some amazing things with the Shapeoko.
Go to the forum https://community.carbide3d.com/ and check out the Gallery.
When I bought the Shapeoko I was checking out a lot of machines, Xcarve, Openbuilds (Ox) and several others. What the Shapeoko has over some of the others is great customer service. The Shapeoko and several others are belt driven but I have not found that to be a drawback for a hobby machine.
Many of the folks on this forum that are CNCer use pro level machines and are comparing the pro machines to hobby level systems. If you compare apples to oranges and you are a pro user of course they poo poo the hobby machines. If I had $10.000.00 to $50,000.00 dollars I would not look back but I dont have that big of a budget. Take a look at the Shapeoko machines and compare the forums of openbuilds to Carbide3d and there is a big difference in support.
I just want to warn you about CNC machines.
One third of you budget is to buy the machine.
The second third is tooling like bits and material and finishing supplies
The next third of your budget is software. Many like Fusion 360, Vetric and there a bunch of opensource and free CAD/CAM software. With the Shapeoko the Carbide Create and Carbide Motion are free. X carve also has a free CAD called Easel as well as a paid Pro version.
Lastly there is a tremendous learning curve. The curve is steep but a normal human can handle it. There will be a lot of time learning the machine, software and watching tutorials on youtube.com and other places.
So if you cannot make the commitment to learning how to CNC dont start. It is time consuming and expensive and there are a lot of CNC project machines that are started and/or finished that are collecting dust in a garage with your significant other barbing you about spending so much money and not producing any thing.