Dry-in a roof with a temporary repair that will last six months or longer. This allows the old house owner time to carefully figure out what work needs to be done and to avoid paying a premium for repairs. An instant weatherproof patch can be made by draping large tarps over the roof ridge. Tightly fasten at edges. Use heavy duty tarp from agricultural supply house. Use exterior-grade plywood of same thickness to patch missing roof sheathing.
If outer-most roof material is missing, install 30-to 90-pound asphalt impregnated roofing felt. Nail it every 6 inches along seams with felting nails. The 90-pound felt will last up to two years. If only 90-pound roll roofing with mineral face is available, install with mineral face against the sheathing. Heavy felt is a good base for fiberglass shingle roofs. It must be removed for tin roofs.
Wire or tie up loose- or damaged gutters and downspouts to help carry water away from the house.
Remove trees from house before repairs begin.
Save architectural fragments and building materials, even if they are not from your house. These may prove valuable in restoration efforts.
If wood floors receive water, wash down with fresh water. Floorboards may warp as floors dry. Do not use heating, air conditioning, or other forced drying measures. Be patient. It can take several months of drying before a floor is ready for refinishing.
If interior wall insulation is damp, take it out via removal of the baseboard. Let interior wall dry thoroughly. Clean mold and mildew off walls by scrubbing with a weak solution of Clorox bleach and water.
Check for loose plaster and either remove or resecure in place with screws. Mark and save decorative plaster pieces that have fallen.