Step one: document and stabilize
Record what you're seeing, stop further damage if it's safe to do so, and note when it started.
Step two: assess the whole house
The visible spot is rarely the entire issue -- water entry, humidity, material condition, containment, and a post-work check all belong in the plan.
Step three: put the scope in writing
Spell out prep, protective measures, materials, access, permits, testing, cleanup, finish work, exclusions, and how changes get handled.
Step four: weigh the proposals
Check credentials, then compare the reasoning behind each bid -- not just the number at the bottom.
Step five: confirm closeout
Make sure testing, cleanup, documentation, warranty terms, and any ongoing maintenance are all accounted for.