You want to treat it like new construction as Villa said the roof, windows re-sealed, re- installed or replaced, exterior doors re-sealed, re-installed or replaced. Electric outlets and vents to the outside should be updated. If the siding is to be replaced, I would remove it and repair the outside of structure and install housewrap to make the house water tight.
Close inspection of perimeter drain a foundation waterproofing for a dry basement or crawl space.
Close inspection of the wood floor from below, joists condition and sized to your new needs? sill plate condition.
Working inside and out is common for the rough work like plumbing and wiring and of coarse framing.
The house wants to be watertight before installing insulation and any other finishing inside.
You should be working with permits, that should require inspections on the framing, the plumbing, the wiring, before the insulation and vapour barrier if required and then you are cleared for drywall.