How much data do you need at that farthest point? Most power line adapters (such as homeplugs) don't like traversing the fuse box from ring main to ring main, but better powerline adapters may do a better job. If you do go with a mesh, then the trick is to get the nodes as far apart from each other while still maintaining the maximum connection speed between them - and too many nodes can actually slow things down. Final point, especially if you have solid walls, you'll find that WiFi penetrates the ceilings and floors better than the walls, so zig-zagging the nodes up a column of stacked rooms can often be the best solution.
I only learn by making mistakes and owning up to them - boy do I learn a lot!
