Check in time was at 15:00, arrived at 14:40 or so and waited outside as the lock box did not have the key. Around 14:45 the cleaning lady shows up and said that she needed 40 minutes to clean and requested us to come back later. We had just been on a long flight and wanted to rest but we were unable to at our required time check in.
My friend slept on the leather couch at the Airbnb and was bitten 4-5 times while sleeping, yes all doors and windows were closed. The next day, night he checked himself prior to going to sleep and he had a previous 4-5 bites from the night before and nothing from the day of walking around Madrid. That night, he got another 4-5 bug bite when he woke up.
The master bath has a full shower and tub, when I went to take a shower I noticed the drains were probably due to many guests hair. As the shower continued, the water went further up the tub, due to improper drainage. I had a few articles of clothing on the floor next to the tub towards the back of it, there must be a whole somewhere at the base of the tub as my clothes on the floor got wet.