I share a roof with my neighbors. Two years ago they replaced the old roof with a new one on their side. I would have happily shared the cost of a replacement on my side but wasn’t consulted. Would a leak from their side happen immediately. Theirs is still used as a garage but mine was converted to extend into my kitchen many years ago. My roof is old and will need replacing very soon but it didn’t leak before but has developed a leak this winter. I have attached photos. My roof is on the left. Thank you.