The top priority is addressing a leaky roof, as delaying this repair can likely result in issues such as mold, mildew, rotted wood, or water-damaged ceilings, with even a minor roof leak potentially taking months to manifest through the living space ceiling below.
Typically, the sequence of work for most renovations involves starting with stripping out and removal, followed by structural tasks such as floors, ceilings, and walls, and then proceeding to the first fix work, which includes plumbing, heating, and wiring.
You can consider the following steps: discuss the matter with contractors you have collaborated with, search for your contracts, gather affidavits from neighbors, review permits you filed with the town for improvements, locate any saved paperwork related to purchases, and examine old bank statements and credit card statements.
A home improvement contractor, as an expert in construction, is qualified to provide guidance and oversee the entire project from start to finish.