My wife and I stayed at Guys place for about a month while we searched for a permanent place to live (we had just moved to Hawai'i).
The apartment was fine, the property was beautiful. The location was very good, five minute drive into Hilo, though not really walkable, and a good jumping off point to get to anywhere on the island. We never met Guy or his family, they live on the mainland, but he was pretty responsive through the app messenger and check-in was easy (key code access). Seems like a nice guy.
The apartment we were in is sort of half above ground, half basement. There is a small kitchenette, full-sized fridge but no oven or range, though there is a double burner hot plate, microwave and convection toaster oven, so you can cook a bit. There is one bedroom with two large beds in it, (no door though, so if you need privacy be aware). There is another Airbnb rental unit directly above, as well as permanent tenants in the adjacent/connected house. You can hear both a bit, but not really enough to disturb us.
There is one parking space for the unit we rented, which can be a bit tricky to get out of, but I managed without a problem. Does not seem to be a second parking spot though so don't bring two cars cause there is no street parking anywhere nearby.
The neighborhood is very nice and the property is really beautiful. Great location (you need a car, but that's true almost anywhere on the Big Island). Drive into Hilo Town in like 5 minutes, go north to the Hamakua coast or Waimea in an hour or so, go south to Puna in about an hour, or take saddle road west to get to Kona side in about 90 minutes.
Overall, not the most amazing apartment, but not bad at all, and the property and location were great, which is more important in my book, esspecially if you're on vacation in Hawai'i. You shouldn't be spending much time indoors anyway!
Mahalo for the stay, Guy.