This very much depends on what level of candidate you require, and the type of projects on which you intend to work.
With an employer grant of up to £3,000 for companies with fewer than 1,000 employees, the most financially viable option available to you is to take on an apprentice. The downsides to this option are the large commitments required to nurture and assist the candidate with their self-development.
A more experienced option would be to consider a graduate coming off a training programme, as these are typically looking for work experience and any opportunity to prove their worth. You like them; you can continue to hire them.
If you’re working on a project-basis, a contractor may be a more appropriate choice. There are plenty of flexible staff available who are willing to be committed to projects from short to long term.
Speak to your recruitment company about all of these options in order to find the one most appropriate for a startup of your size and speciality. If their service is tailored to the level that it should be, they’ll understand both the risks and rewards associated to different recruitment options.