A few days ago we saw a weasel scuttling down our rear garden path away from the house.
Didn't think too much about it at the time as we'd seen one in our garden a couple of times last year, and just thought it was passing through.
Two days ago we saw the weasel coming along the rear garden path towards the house, veered off left towards the sliding door to our ground floor extension (currently our office) and disappeared underneath the bottom wooden door sill. We watched for several minutes and there was no sign of it, and figured it must have found another route around the perimeter of the house and disappeared again.
Prior to this I'd heard a scratching sound above the ceiling of our office and figured a mouse had got in somehow.
However, yesterday morning I was looking out of the same door and saw the weasel appear from underneath the door sill. It got fully into view, stopped and turned to look at me, then disappeared again. Long body, about 6 inches, red/brown colour and a white chest. Very cute face. Definitely a weasel.
On closer examination of the door from outside, I discovered a very small gap - no more than 2 inches wide and ¾ inch high. I wouldn't have thought it possible for it to get through the hole.

Haven't heard any more scratching in the ceiling for well over 24 hours now so guess the weasel has vacated the premises. For the time being at any rate.
When we put our house on the market we don't want any potential buyers hearing critters scuttling about in the house. So, this afternoon I took the opportunity of plugging this hole to stop further visitations, having assured myself that I wasn't trapping it inside and literally sealing its fate.
I'm keeping an eye (and ear) on alert to make sure it doesn't find another way in. Phew!
Laurie.