Moved to new flat, very strange wireless issues

First I just had my laptop before moving in furniture and it kept not recognising either of my phones or my mifi, or it would show then keep dissapearing.

Then it finally worked, and I moved it to kitchen where it got a 5 bar H signal and it worked for about 3 hours at a good speed till battery died, I kept dongle in same place and just plugged in charger but now nothing, after 30 minutes gave up and went back to old property.

I moved things in today and identical problems also on my Windows 7 desktop(also has a N card in) the ONLY way to get it to work is to put the dongle touching the aerial even then its around dial up speed.

Anywhere else and it shows either zero signal or 5 bars but fails to connect most of the time or if it lets me connect it stops working after a minute.

My laptop picks up a few other neighbours networks with identical issues, one moment 5 bars then 1 bar or none, could it be a neighbour is tethering to their pc and its interfering? As one of the strong signals I get is AndroidAP, 5 bars on laptop.

Could be the number of WiFi networks in the area or something locally creating interference, e.g. video sender