I'm sorry you had such a disappointing experience @Barry173 .
If having a detached place was important to you, I would suggest always checking that the property is, as a cottage doesn't necessarily mean a detached property.
Many thousands and thousands of council houses and flats were sold off unfortunately in the UK from the 1980's so it wouldn't be out of the ordinary for some Airbnb accommodation here to be former council housing. (But I see you are from the UK so will know this).
Looking at the listing, it does appear quite basic, but has a price that reflects this and issues such are the curtains you mention can be clearly seen along with the basic furnishing.
And of course the garden is not going to look like a summer's garden in the middle of winter.
If facilities and amenities were missing that were described in the listing, and you notified the host immediately as you say, I am suprised that a partial refund wasn't considered. Can you give more information on what particular facilities and amenities weren't there ?
Glad you are enjoying your latest trip.
I would say read a listing carefully and look at the reviews and ratings. Stay with long established, superhosts who have five star reviews.
The vast majority of Airbnb's are as described.