Dear All
thank you for leaving [house address] in a generally reasonable condition at the start of the summer.  
However, we were disappointed to find the bins left full, lots of recycling waste and in particular the food waste bin full of rotting rubbish and maggots and flies.
[wife name] cleaned it out, the smell was so disgusting, the slurry and rotten material was repulsive.  It made her vomit.
This shows a lack of consideration for us and the neighbours who had to suffer from the smell and the flies.
We point this out so that you remember to dispose of your rubbish properly in future wherever you are living,
regards,
[husband name] & [wifes name] [landloads surname]