We have a long garden. At the end of it is a small row of terraced houses. They don't have car access. The end one backs onto our garden. It was bought in 2022. Someone started work on it, but it has been left for a year or so. The door is open. It needed doing up but isn't habitable at the moment. The fence has come down between our two properties and you could get straight into our garden through theirs. I was thinking of asking their neighbours if they know anything. Should I be concerned?