CNC Electrical cabinet size?

I am looking for a relatively cheap electrical cabinet enclosure to house my DMM power supplies and related equipment. I see some are using a 24x20x12 size cabinet, but they are difficult to find.

What size can I realistically get away with?

Hello Kevin,
If you are like me, you hate paying for enclosures. The least expensive ones I have found are from Wolf Automation. You will have to check the dimensions but here is a link to a series of enclosures I have used:
BC-AGP-203015 | Boxco | Enclosures (wolfautomation.com)

Finished Cabinet:

If you have something like a Bambu 3D printer, you can actually print your own:

i would stick with a steel enclosure personally and you can get away with one that is 10" deep with the DMM drives. i would probably go with a 24" x 24" x 10" or 12" depth. since your dealing with AC power you have to have room for line reactors and EMI filters on top of everything else. So if you are using the 240V DYN4 drives i have 4 in this case i linked below.
Electronic Enclosures & Electrical Box Size Search | Polycase

here is another one that is cheaper yet and 12" deep i did not think they had them over 8" deep but i was mistaken. i have bought my last two enclosures from Vevor and what makes these ones nice is they have a panel that bolts on with a seal so when you go to run you wires you only have to deal with putting some holes in a small panel section rather than trying to deal with the whole box.
VEVOR Electrical Enclosure, 24’’ x 24’’ x 12’', UL Certified NEMA 4 Outdoor Enclosure, IP65 Waterproof & Dustproof Cold-Rolled Carbon Steel Hinged Junction Box for Outdoor Indoor Use, with Rain Hood | VEVOR US

I agree that steel is a better way to go, but I have had no issues with plastic even with an AC servo enclosed in this smaller enclosure.