Overall, my partner and I had a good experience at Nate's place! Please note that the toilet may take some getting used to (we were a bit taken aback by it initially), however, Nate is very communicative and friendly. If you have certain digestion issues...it may not be a bit tricky. We, too, love to be eco-friendly :)
The bed is VERY comfortable, so you will get a good night's rest. The place is small, but there is room to store luggage under the bed.
My only suggestion would be to improve the wifi. We did inform Nate that it was spotty and he gave us tips to fix it. While it did not improve the wifi, we were not in the room enough for it to be an issue.
I would recommend Nate's tiny house for those interested in a no-frills, short stay in Austin.