Keep in mind

WiFi n has a much stronger signal than a/b/g, but your connecting computers would need to support n as well

Radio travels in straight lines. This can mean if it hits a wall or a floor at a low angle of incidence it is trying to travel through 1 or 2m of wall or floor. put your head by your base station and look to where you will have your laptop and imagine what the straight line passes through.

You certainly want the WiFi base station at least 1m away from any DECT wireless phone base stations.

Getting a router to work well for months or years is quite a tough challenge. It is best to assume that you router is going to fail at this and find some way of power cycling at a convenient time for you. Perhaps a time switch between the plug and socket set to power down at 4am every night for a few minutes (or hours if you want to be a little more green)