2001 Megane Convertible Leaking

My 2001 Megane Convertible owned by my mum since it was two years old and by me in the last three has a issue with water getting into the car somehow causing puddles on the drivers side. It's be happening on and off for the last two years but never bothered my mum, however it bothers me. It's not coming in from the roof or around the windows due to multiple bucket tests and i refuse to take it to Renault, anyone know what might be causing this issue?



You can see what it looks like here;

http://ift.tt/1oO4l5d