You can see the pricing here: https://www.lensrentals.com/rent/nikon-z6 It is a pretty expensive rental, but, that's because it is brand new.
I usually don't splurge and rent the 'latest & greatest', and I always buy used or refurbished equipment, but, I was hoping that the Z6 might be the hybrid camera that does a great job at both stills and video, so, I was anxious to handle one. Reviews are useful, but, the best way to know if a camera will work for you is to have it in your hands.
I have a D750 that I use for my daughter's swim meets. I need a FF sensor since some of the pools are not very well lit, and I need a minimum SS of 1/800 to freeze the swimmer's motion. Before I got the (used) D750, I tried using my u43 gear for swim meets, but, it was just too noisy. I could get some OK shots if I slowed the shutter speeds down to 1/200 - 1/320, but then the swimmer's arms and legs were always blurred (but sometimes the swim caps were sharp). A couple years ago I rented a d750 and 70-200/f4 for a league champs swim meet, and was amazed at how mu ch better the results were than with my GH3. Almost every shot was fine. BUT....it is impossible to take useful video with the D750. So, at the next championship meet, I rented a Sony a7r2 and Sony's 70-200/f4. It was nice to be able to take good video with the a7r2, but, what a let down as far as performance! It was SLOW AS MOLASSES! I missed way too many action shots because the camera was buffering and not ready to shoot. This especially happened if I took a video clip and then wanted to take some stills. So, after that experience renting the D750 and then the a7r2, I watched e-bay for months till I got a great deal on a D750. Since then, I have slowly acquired some nice (used) Nikkor glass. I now own the 70-200/2.8 G VR II, and the 300/f4 PF and they work really well for swim meets.
I was hoping that the Z6 would be able to do as well as the D750 in stills, and also give me great video, in one camera. I've not done a lot of testing with it yet, just one day. The video looks quite good, BUT, the AF-C for stills is a huge letdown. In my opinion, based on some testing I did today, the Z6 will not satisfy my use case of action photography (swimming). The AF-C is just very poor. Hopefully, in a year or two Nikon will release a mirrorless camera with great AF-C, or at least one that is as good as the D750, but, right now...
Sorry to ramble on, but, those are my first impressions. I'm quite disappointed by the continuous AF on the Z6.
For a simple AF-C test using [dynamic area AF], I tried to take a sequence of shots of license plates on passing cars on a residential 25 mph road. I got very poor results from the Z6. With my D750, I get almost 100% in focus (except for when the cars are VERY close). With the Z6, the in focus rate was more like 15-25%. I tried different AF-C modes like [Wide Area S] and [Wide Area L] and got similar results as with [dynamic area AF]. Very poor rate of shots in focus. So, I don't think I would trust the Z6 for action photography?
Apparently that is the same reaction from Gordon at Camerlabs (but his review was of the z7, I was hoping the z6 would have better AF-C)
https://www.cameralabs.com/nikon-z7-review/
As an aside, for AF-S the Z6 did fine, but NOT AF-C.