Printing very dark, newbie

Your Ricoh is a PDF Direct/optionally Postscript capable Printer, and has many setting related to Color Profiles. You need to check your printer settings when printing from Acrobat, especially those for ColorSync (if on a Mac, it should allow you to pick the proper profile for your Ricoh), and also one called CMYK Simulation. make sure these are set appropriately and are not "off".

You can submit PDF files directly without having to "print" them from Acrobat, either through its web interface or off a USB stick... have you tried that?

Make a PDF with NO color conversion first, then submit one of those and see if it makes a difference. If it comes out the same, then there's definitely an incorrect setting in your Acrobat print dialog.

I've switched between RGB and CMYK in inDesign with no difference.

Hi @Deon28419597dmet , InDesign doesn’t have a document color space, the objects on a page can be a mixture of CMYK, Lab, or RGB color spaces. Composite printer typically want RGB color—the print driver makes the conversion to the print space. When you export the PDF, have you tried converting the color to a uniform RGB space? Set your Export>Output tab to something like this:

@rob day Will eat me for this 😄 

But I think it's because you're assigning profiles rather than Converting to Profile. 
But Rob is an expert in this sort of trouble shooting and I don't want to sully the waters with my shortcuts to the answers and quick workarounds.

There's probably a lot to investigate here to sort this out.