What do the reviews on Booking.com say?
In addition to the rating and the location which you can easily see on internet, I would check the hotels with lot reviews (by their listing start time on Booking.com), and read All recent reviews, especially the ones related to the particular room/apartment I am interested, about the noise level and if the bed is comfortable (as we are very sensitive to those), and other facilities we use. You should know your needs better than anyone else.
I noticed one interesting live feature of Google maps recently, it marks the busy areas with yellow color (by active cell phone counts, I guess), and the busier the darker. One can use it to get a feel of the area, areas with more attractions, restaurants, shops, should be of dark yellow during daytime and stay yellow at night, especially in Spain. 🥵😉