It's possible they have the skills you need but their time isn't fully utilized, so they can fill time with working on your projects rather than looking for more clients.
Maybe something like retaining 25% of their time for your projects could work. If you need more than 25% of a person's time, then maybe find two people with different skillets (although coordinating could be more difficult).
Maybe something like retaining 25% of their time for your projects could work. If you need more than 25% of a person's time, then maybe find two people with different skillets (although coordinating could be more difficult).