Hi Justin,
have a read of this thread here
viewtopic.php?f=1&t=47317
I know it's more from an addon perspective, but some good in regardless.
A lot will come down to how mush they are paying for that service now and how happy they are with what's being done.
Versus
What do you need to charge for you to make it work and make you money and what level of service you can deliver at that rate.
If they are paying cheap, but frustrated, you may get in at a slightly higher rate and fix their complaints.
If they are happy with their current service regardless of costs, then you're chances dropped right off, but still worth putting your info in front of them.
If it's a potentially valuable contact, there's nothing stopping you asking for a shot at a problem area for free or at a low cost to show them what you can do.
John