The solution will require a modem, a PFSense box and an access point, at least. This is again some cables, at least three adapters and more space requirements.
I can manage a much complex setup if I need to, but space and noise is at premium, so it won't help in my case.
You can have PFSense act as an access point if you install a Wifi adapter in the box you use as a router. Depending on the square footage you need to cover, you might not need anything else.
Edit: Just saw the bit about thick walls. Sticking to 2.4 GHz might have a better result if your neighbors aren't too close.
The solution will require a modem, a PFSense box and an access point, at least. This is again some cables, at least three adapters and more space requirements.
I can manage a much complex setup if I need to, but space and noise is at premium, so it won't help in my case.