This happened to me. Landlady had been sent my profile by neighbours and everything. She didn't disclose this, she just said she wants to "inspect".
She came and had the most disgusted and condescending expression on her face and I knew she knew. It was a very wealthy neighbourhood, the most expensive in Australia actually and my studio was right at the end of a cul-de-sac with it's own private entrance, on top of the main house (also rented) on a cliff. So she said to me that wealthy people don't like seeing "randoms" in the area and I should stop bringing them around.
The flat was spotless and I had bought some new pieces of furniture and she commented about how I had arranged the place to separate my personal space from my work place since I lived there. She let me stay for 2 years and never spoke about it again. In the end, she was very nice to me, maybe she felt guilty, I dont know.