In general it's hard to scale an hourly business. However, here are a few suggestions:
1. Offer a lower rate tier where you can capture a lot of people such as group coaching. You'll need address topics that are general to the group, and make sure that the people within the group are similar enough, but don't feel like they're competing with each other.
2. From the group coaching you can suggest people upgrade to a higher price such as the $4K for 6 1-hour sessions to address specific needs and provide the high touch individualized attention they're looking for. However, I'd still be cautious about letting people know how much they're paying for an hourly rate.
3. Can you productize this service in any way? Most businesses scale by productizing their information. If you can create learning modules for people to go through, then you can have the complete work on their own, then use 1-1 time more effectively.