The main reason I was considering a full-automatic tempering machine was to have a dosing pump. I then found Hilliard makes one that which costs significantly less, though still around USD$5,000.

Researching various pumps it seems that peristaltic pumps could be a very affordable way to hack it together. There are even a few people 3D printing pump heads through which you could put a food-grade hose.

Are there other cheap options I should be considering? Has anyone gone the DIY route and have advice to share?

You can try this thread: https://www.thechocolatelife.com/clay/group_discuss/1267/diy-depositor-is-it-possible

Ah, thank you! For some reason this didn't show up in my search results.

What information did you find about peristaltic pumps? I was hoping to find/buy a cheap one but no luck. Is printing one the best way to go?

I found a model for about $350 at simplypumps - it's hard navigating the different models online and they seemed the most approachable for beginners. I've had a 3D printer but don't like the look of the material and I'd also need to buy a motor; I prefer having something that should be resellable.

Which one did you go with? Can you provide a link?

Sounds like a fun project!!!!  Let us know what system you come up with...

As soon as I build the other stuff, I intend to get the  PM600 .

Other stuff meaning: a heated container and a vibrating machine. Yesterday I realized putting chocolate in moulds isn't the actual bottleneck just yet. I spend a good chunk of time manually removing bubbles and feel the need to work faster because chocolate is starting to crystallize.