Leaning In to Buy Side Investor Client Business

Hello All, 

Does anyone here do the lion share of their business working exclusively with investor clients? If so was that always the case? If not how did you grow and develop that part of your business to the point it was the main part of your business?

I am thinking up content which I can provide to my base clients (And how to acquire new clients with it as well) Which clients would find most valuable and beneficial leading them more likely to buy or refer me. 

Looking forward to hearing what has been working for you!