They are hit and miss. No tech I know will tell you it will fix it. And some won't buy and try. Tough crowd?
It has nothing to do with placement but everything to do with getting more access points. Only your newest networking shops for a stronger router or moving "one" around.
Sorry but there is no magic here. Add access points, wire back to the source or try powerline bridges.
Bob
I have recently moved into a apartment style building that offers free wifi. The floor plan for the 4 floors are all the same. Using the stairs or the elevator you come into the communal kitchen and lounge area. Now the router/modem is on the second floor lounge area and we do get wifi in the 3rd and 4th floor common area.
The issue is the wifi never reaches anyones rooms even on the second floor. it might have to do with placement. The common area is usually located at the centre of the floor and everyones rooms are located along the outskirts of the floors and even on the second floor people seem to have a hard time connecting to the wifi. In my room on the 4th floor the network is not even visible but it is in the main area(although weak).
The residents are petitioning to get the wifi improved. I am wanting to take it one step further and propose a solution as well to the owners of the building. I was looking into wifi range extenders but don't know anything about them. If anyone can help me out that would be great 
Chowhound
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