Personally - I would look at other similar forums to see what kind of policies they have implemented.
Like any saturated industry you will find many so call "businesses/companies" that will do anything for a few cents to a dollar that turn into forums for spam, fake reviews, and useless posts to indirectly spam their signature.
So, my suggestion...
- Strong policies from the start for members to follow to keep it clean and trustworthy.
- Strong Categories
- Choose moderators that are trusted and will follow & enforce guidelines
- Be part of the conversations
- Encourage people to share knowledge
- Welcome new members and encourage them to introduce themselves (seems little but it can go a long way)