Hi, Thomas. Thank you for you quick reply. I did go to registry to get the title. Unfortunately, it only showed the name of the owner, but no contact information. I will try online title search to see if there is any difference from the one I got from registry. I will try to fix it by myself...

Long story short, the next door is a retailer shop, and the building has no eavesdrops, which results in rain leakage to my basement, especially in summer. I met the tenant of the next door and an officer of the town last year, and we agreed that extending the concrete layer to direct water away...