Why so cautious? Are you not hiring programmers at-will? If Im not performing on par with a team, Id leave no hard feelings. The reason I applied is im highly interested in building tools for educators, and currently run a business that sells such tools.
To "try them out" you have to teach them enough about your process and code base to be useful. That still can take significant amounts of time. The primary investment isn't money, it's time.
