US Registration & Referrals to Counsellors

Hello all. My understanding is that as a firm grows and has >20 US person clients but <$100m AUM, state registration is required. My questions for the group are:

1. Is anyone willing to share their experience with this process?
2. Who are some good contacts that offer US Compliance Counsel or RIA Compliance Consultants that you can provide?

Any insights would be greatly appreciated.

Thanks everyone.

-Cam