Bring the insight, not the specification. The most useful thing you can tell a studio is who has the problem, what they do about it today, and why that is not good enough.
Expect six stages: validate, blueprint, brand, build, launch, and run or hand over. Each one should end with something you can open (a summary, a prototype, a login), and a decision that is yours to make.
Decide early who owns what. The code, the brand, the accounts, the data and the product's domain should be yours. Ask for that in writing.
AFTERCODE · GUIDE · [[CONFIRM]] author and date