Ok, first off they don’t use cartridges

There are two kinds, FDM and resin. FDM uses plastic filament to print, resin uses UV light to cure the object into an inverted print bed.
For models with high detail FDM isn’t viable, the layers aren’t fine enough. FDM is good for large things like Titans or terrain, things that are large enough to be sanded and finished enough to hide the layer lines.
Resin, once painted especially, looks identical to a GW miniature.
It’s around $30 per liter of resin. If we were talking space marine sized you could probably get 150-200 or so out of a liter. It would all depend on if you’re printing them in 1 piece or in multiple pieces to assemble later on. The more pieces, the more supports needed, the more resin wasted printing the supports that you’re just gonna throw away when you’re done.
The program you use to prep the files for print shows you how much resin your print will take and how much that costs you.
For a larger model like a Rhino I’d print it solid, instead of a hollow model or a kit, and that would cost me around $4-5.