Sony a7 III (ILCEM3K/B) Full-frame Mirrorless Interchangeable-Lens Camera with 28-70mm Lens with 3-Inch LCD, Black

I am a noob in photography, was lucky enough to have some money and I decided to go for this camera to start with astrophography.
Out of the box, all things included as stated, battery works, lens (28-70mm) included, usb cable, adapter for battery to charge and obviously the camera, all of them arrived in what seems to be new condition, though the box did not had a tape seal (usually electronics have a small transparent seal on top of the segment of the box you use to open it)
Upon using the camera I noticed an issue, with autofocus mode on, sometimes when I tried shooting with lens at 70 mm at subjects at bout 9 – 10 feet away indoors, or even stars at night outdoors with crop mode, autofocus would get me out of crop mode, if I activated crop mode again, autofocus would stop working altogether and then the function would no longer “exist”, if I pressed the shutter release button halfway (all of these with camera place on auto mode), to try and get the autofocus to do its job, nothing would happen, then on the screen I would see the ISO at 12800, if i released the shutter release button the iso number disappears, if i press the release shutter half way again, the iso number 12800 appears again and it stays there until i release the shutter button, if i take a picture it is all blurry. I then tried to use the manual focus but nothing happens, I remembered I had to turn the manual focus option on, so I get into the menu and the focus mode option is greyed out, if I try get into the option an error message “your lens is not supported or its installed incorrectly” shows up, only way to go is to shut camera off and turned it on again, which will return autofocus to work, but if i repeat the exercise it just stops working all over again, sometimes even without crop mode/zoom mode on, just by going from 28 to 70 mm on the lens, or even mid way, maybe 40 mm or 50 mm. Sometimes even the camera would pull me out of menu screen, I would click menu button, I am trying to navigate menu, then you can hear the focus mechanism moving and camera pulls me out of menu screen o regular screen, I have to press menu again, sometimes to be pulled out of the menu repeated times
I re installed the lens (white dot with white dot, turn until click noise) golden plates on the lens are clean, did this 3 times, nothing.
I called Amazon service, friendly person who quickly contacted me to Sony, and this is the part I did not like. We went through basic things to try and fix the issue, including resetting the camera, after which the issue presented itself quite quickly, so the person at Sony (again, a very friendly and helpful person) told me I needed to send the camera back to Sony for service. I asked him if that given this was a brand new camera (I received this this past Tuesday Feb 9th 2021, today is Sat 13th Feb 2021) I would get a new camera (replaced) he actually told me that at Sony they only offer repairs, and if the cost is out of the warranty I would be charged for the replacement?!
I am not entirely sure if this is true or not, but if it is, this very bad business practice to say the least, so I pay for a brand new camera, which comes defective, so I am not getting what I payed for in the first place, and they then tell me that there is the possibility that I would have to pay EVEN MORE to actually get less (it would not be a new camera now right? it would be basically a refurbished one with all the risks that implies) than what I ALREADY payed for in the first place! I payed for a new camera that is supposed to have all the features and functionality advertised by sony/amazon on their webpage, and I did not got that, and again, I might be forced (because if I do not pay I would not get a working device…..so basically I would be forced to pay if I want anything ressembling a working camera) to pay more (you pay for a new working product, you dont get one, and then to get a working “not new anymore” product you sometimes have to pay more than what you already payed in the first place) . I would strongly recommend to stay away from this brand, who knows, in the future I decide to buy an expensive lens from them, and then if something is wrong, they only “repair” a lens, maybe even after asking for more money from me. No Sony/amazon, shame on you, bad business practice.
Again, I want things to be clear : they HAVE NOT asked me to pay anything YET, as I just send the camera back to Sony, but the Sony person I spoke to made it very clear that they do not replace cameras with new ones if you receive a faulty one, they only “repair them” and that I MIGHT even be charged in some cases.
This is my experience with the Sony a7III, and Amazon – Sony regarding this product, not good, not happy.

Update 2/19/2021:
1. I spoke with the same Amazon representative who was present the day I spoke with Sony, and he assured me that I CAN return this product to amazon if not satisfied (which I most likely will immediately do after receiving it back from tech service).
2. The camera did not went to Sony directly, it went to a tech service that from what I understand, is the one Sony works with to repair/service their cameras.
3. So far, no one has asked for any extra payment.

Super Amazing Camera
Best In Planet for Cinemats and Photographers, Just Buy it and See the Magic.

Fantastic! And I am a tough judge. Made me consider abandoning my Fuji system with 11 lenses…

The only thing is it’s ridiculously configurable, so you need to spend time to create your own ‘My menu’, otherwise you can never find anything. But you can use it as-is and get fantastic pictures, or spend time, get deep, to make it your own. Anything in between maybe a bit frustrating.

If I were looking at single camera only, Fuji still has a touch nicer colours directly as JPEGs (Sony’s are very good, Fuji’s are great), and if you shoot in good light only, Fuji may still be your preference. Most lenses are more expensive than Fuji’s APS-C, so that may be a factor, except that Samyang and now Tamron are doing bang-up job bringing great budget lenses. Samyang 35 2.8 is a steal, and I hear great things about Tamron 28-75 2.8, so between these two and Sony 28 2.0 you have a whole system. Also available for this system (only!!!) is a Techart Pro that allows you to use manual focus Leica lenses as autofocus!!!, and then you can adopt any vintage lens to Leica mount and have auto-focus, so that may be a big factor too

 Great Product . Pictures are great won’t be disappointed by the quality. Multiple setting functions. Only down fall is it did not come wit a Memory card

If you are reading this, chances are you are considering full-frame mirrorless. Truthfully, there are a lot of good reviews that discusses the goods and bads about this camera as it is a very popular model. For me personally, the biggest benefit for going full-frame is the quality of lens available to full-frame cameras. I used a Nikon D5500 APSC camera for the past 5 years before acquiring this one. Aside from the quality of lenses, I think there are a few noticeable differences:

1. The Auto Focus system on this camera is truly amazing. Truthfully, if you overexpose or underexpose a couple of stops, no big deal, you can correct in post-processing easily. If your aperture is slightly off, no big deal, you may hardly notice. But if your focus is off, the photo is wasted and it is very difficult to notice until you load it to a computer to see. The auto focus system on this camera is very snappy and it is a huge leap for me compared to what D5500 offers.

2. The feature of what you see is what you get. I would consider this to be a very nice feature for mirrorless cameras. This feature is particularly useful for night photography as you can crank up ISO when framing initially. It also has the feature of highlighting the area in focus so you don’t need to take unnecessary risks.

3. This camera has a built-in self-timer. This maybe considered as a duh feature but before, I had to use a remote control with my D5500 for star trail photos.

I am still learning about the features and continously being impressed by them. But if you are considering full-frame but not sure. I would recommend going for an “entry-level” full-frame mirrorless like this one. For most use cases, pairing this with a G Master 24-70 will give you plenty of fun.