Ask HN: Client Services as a Service?

My sister recently left her last position as a client services director for a medium-sized start up and instead of jumping back into it at another company is considering offering her expertise up in the form of a consultancy.

I'm trying to help her figure out the viability of such a business. Her theory is that many many young startups need client services but either (A) don't know it yet, (B) don't have the money to hire for it, or (C) don't have the need for someone doing it full time yet. This is where she and her partner would step in.

What does HN think?