Full-time, part-time, short-term, or freelance
Don’t just think you need to employ someone on a full-time basis on a full-time salary. Why not employ someone part-time to start with until the role develops? Or a seasonal worker on a part-time basis just to cover your busiest times of the year? Or a specialist freelancer for a particular project?
Whichever you decide make it very clear from the outset what the role is, what the terms of the appointment are and how long it's for. Put this writing and get you and the person you're hiring to sign it.