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

$75/day = $2,250/month

No, doubtful you’ll find:

1. an audiophile + 
2. can afford $2.3k/month +
3. Choose your option rather than common alternative to purchase.

If one saves for 7 months, can purchase own new unit - much better than what you are offering

Also, with renting comes wear and tear, and you may run into trouble if they drag their feet on returning

Testing DAC to test then return asap might be worth it to some who are specifically interested in your particular DAC,

Personally, I wouldn’t want the risk- if something goes wrong with the DAC, who’s going to pay to fix, them?  It’s one thing being right, quite another to make them pay for repair.

Depending on if it was already broken in and how much shipping with insurance was, I might give it a try.  But I really don’t want to pay $75 a day to burn in something or pay an additional $500 in shipping costs.  See if anyone within a couple hours drive from you has what you are looking for.

Thanks for all the brutal replies. Lots of shade, but I still like the idea. This business model is not without precedent. 
 

Food for thought - I can rent a Leica M11 camera (MSRP $8000) from Lensrentals.com  - $67/day for 7 days. They don’t take a deposit, but do offer optional insurance to limit my liability. It’s shipped to my house in a Pelican case (roughly the size of the Tambaqui Pelican case) for $25 each way FedEx 2 day. 

Could I purchase the Leica from a retailer with a 30 day return policy? Yes, but I’d be putting $8000 down and be expected to follow through. I’d rather rent it for a week, decide if I like it, then purchase preowned for a $3000 discount.

No!!!!!!!!  

Great idea if you were a dealer and any rent goes towards purchase. But without that... no. I wouldn't rent one... and you have so many potential liabilities.. No.