Would you rent a $14,000 DAC for $75 per day?

I think you'd be better off setting up a space with said equipment and allowing persons to rent the space.  For instance, I would use a high-fidelity DAC to transfer CD recordings to tape.  Or let's say someone wanted to bring in their collection of CD's and rip them all to a portable storage media.  There are plenty of use-cases one may consider.

But loaning your equipment out by way of logistics?  Just sounds like a great way to break something, lose something, get back a non-working version of what you had, etc.

I once thought about this as a business model but so many scams out there, considerations about equipment getting returned in working condition, etc. 

I kind of wish there was enough interest in audio that say, a music museum could pop up with listening rooms of different grades of equipment to try, have demonstrated, etc., along with exploring music of all known genres to further increase interest.  Would be a great place to visit. 

My fantasy anyhow. 

No.

The value prop is unclear for me. With camera rentals - you keep the outcome, the result - the image. That is the value of the rental.

Renting the component - the outcome and benefit leaves when you return the component. I can’t imagine anything more frustrating than to hear my system sound incrementally better due to a component that I can afford to rent, but not buy, then to regress back to prior performance once the rental is over. It is the exact reason I bring nothing home from my dealer (who is very generous) that I’m not in the position to purchase. I can’t fathom stepping forward then back; I generate too many of my unrealistic desires, audio and otherwise, just fine, thank you very much.

Therefore, renting a component only makes sense to me if I were auditioning prior to purchasing. But there are many avenues today - local dealer (my preference), on line retail with a liberal return policy or direct from manufacturer with a liberal return policy. If this were to be the primary value driver, then, your inventory would need to be current and cover a very wide range of the current marketplace. At the extreme, an inventory equal to a weekend at AXPONA…

Lastly, as a rental service company without a dealership to sell equipment and the subsequent revenue from the sale of equipment (not used component sales), how does this move forward without any real upside?

To prove that it doesn't sound any different than a $200 DAC, yes.