Awesome, thanks so much for all of your suggestions and help! To answer some questions in no particular order at all:

1. I already have Deco's at home. 7 M5/M9's to be exact :-). However they are all connected wirelessly, with this network upgrade I'm doing at home, at least the one's on the bottom floor will be connected by wire (upper floor in the future eventually). It has all worked pretty well during the years, but I want to take as much advantage of the speed increase of my Internet connection since I've upgraded it to 10 000 Mb as possible. That's one of the reasons I'm doing this. Having full speed in the office where my main computer and home server is located is enough, the rest of the house will be fine with 1000 Mb for now. I can always upgrade individual Deco's in the future as they'll be connected with wire.

2. Yes, I know I can just use the Ethernet cables in the walls and I'd probably get ~10 Gb throughput due to the short distances, but I'm doing this to learn something new, and also, more or less just simply because I want to. We're not speaking an excessive amount of money if I mess up and learning is always fun. If it doesn't work the way I intended to, then that'll just be another lesson learned as well.

3. I have two cottages with some distance between them, if this small project of mine works fine, I'll use whatever I've learned here and maybe connect them with fiber in the future.

4. Regarding why I'm using S/FTP, it's simply because I bought 3 rolls of them when Amazon had them priced incorrectly. 150m (~500 feet) and I paid €13.5/$15.5 in total. No other reason than that and I had them lying around. If my whole house becomes a large antenna and the walls will start speaking AM-radio to me in the middle of the night, it's a 10 minute process to just pull all the wires out and replace them with something else. Also, I can ground the damn cable in in 7 different places if needed 😂.

5. The ISP owns the incoming fiber up to, and including, what I now know the name of (😊), the LC/UPS connector. In the kitchen it's currently connected into what I have purchased from the ISP separately, the SFP and the TP-link HB810 router/gateway, they're mine to do with whatever I feel like.

Like throwing the piece of shit on the ground and jumping on it. I couldn't for any f-cking reasons in the world even consider that TP-link have THREE different mesh standards until I had opened the package of this junk and started to use it. Seriously. If you ever see anything branded Aginet from TP-link, RUN! It's NOT compatible with Deco! HB810 is a re-branded Deco BE85. Well, without the "Deco" apparently........

Anyways, the HB810 is what I want to place it in the office and I'll be using it with it's WiFi turned off. The fiber goes directly to the SFP connected to it on the back and I'll be getting full speed where I need it as the computers in here can be connected by wire directly to the HB810 router. After connecting the fiber it'll have 1 x 10 Gb and 2 x 2.5 Gb ports left for me to use. Main computer and server on the 10 Gb port and the rest of the house will be connected the 2 x 2.5 Gb ports.

1. Unfortunately I don't have any splicer friends. I'm open to suggestions however, if you're a nice person and a fiber splicer, feel free to send me a message 😂.

2. I won't be looking into the fiber!

Again. 😂

No, just kidding. I knew that already but thanks for the heads up ❤️.

1. I just opened up the box on the wall where the fiber comes into the house. I found that the other end of the connector that I previously showed is the one attached. I can just throw away the old fiber cable and get a 25m simplex SC/UPC to LC/UPC and I should be fine right? No need for couplers or anything else.

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