So he did the sensible thing and started a Tumblr, collecting pictures from around the world.
"I was househunting and was constantly appalled by the quality of some of the images," he told BuzzFeed. "I stuck some on Facebook along with some snarky comments and it went down well with friends, so I started a blog."
The site went viral that September and has had around 7 million visits to date, with the United Kingdom, Canada, Germany, and Australia providing most of the visitors.
Donaldson, a senior digital manager, insisted all the photos are genuine and from real property sites, from South Africa to Kazakhstan. He added that among his biggest fans are estate agents themselves: "Reaction from estate agents has been universally positive, and many of them have featured the blog on their own sites as an illustration of how not to do it."
A book is coming out based on the blog later this year. Here's a selection, including some of Andy's favourites: