Ask HN: Good templates for documenting software security?

We've been mostly creating our own ad-hoc documents to answer these questions for current/potential clients, but I'm looking for a template that we could re-use and have a company standard document to answering the typical questions we get:

- What data will be collected, how?

- How it will be treated?

- Who is it shared with?

- Integrity in maintenance, period of maintenance, backups, etc.

- Management of access to data, etc.

So looking for templates, anything that works for small startups without going too deep into technical details and standards would be great.

EDIT: format