I live in a small 2 storey home, about 1500 sf per floor. My main problem is that the main router is placed upstairs in the hall and most of the equipment I have is on the ground floor.

I have tried various methods in improving the speed downstairs on the ground floor but the best I could do is about 180 Mbps. My subscription is 800 Mbps. The reason why I want to increase the speed downstairs is because most of my stuff e.g. TV, karaoke, laptops, gaming system are all downstairs. The PC in my room on the first floor averages out at about 650 Mbps and I have nothing much to complain about that, using an Archer TX20U connected via USB 3.0

Then again, all the stuffs on the first floor are working fine with no lags whatsoever. I just want to know that I am getting the highest speeds possible wherever I am in the house.

My equipment:

Fiberhome SR1041Y x 3 (WiFi 6 - 1 as main router and two on the ground floor as mesh)
Deco M5 x 1 and M4 x 2 (WiFi 5) - separate SSID for these as I had them around and do not want to waste it

As you can see, my home is cluttered with all these routers and meshes and I don't mind discarding all of it and getting a complete new overhaul, with a budget of around 1k.

Any recommendations?

Thanks in advance.