When we bought our five acres with it's falling apart old red pine log cabin, we didn't have much financially, so we had to move in, then do the repairs. Until we got the land cleared, and all the holes in the structure located and blocked, we had field rat.
We would be watching TV, or just setting around the house, and all of a sudden, we would notice a big fat rat watching us. They even showed up two and three at a time. Setting in the middle of the floor, just starting at the weird people. The place had been unused for about 25 years, and those rats thought it was their house. Took us three years of diligently plugging openings. Yuk!!!