That sounds like a simplr qiestion Carl but it clearly needs a lot of further thought.
Firstly you have to decide what you want to happen to your business in the future. Are you happy to continue to develope your round to a stage where you can manage it on your own, provide that one-to-one good service and earn a tidy income OR do you have expansion plans involving marketing, extra vans etc and eventually have the staffing levels to allow you to manage rather than do the w/c.
If you say you have the potential to expand in your market place and have the drive to do it then, after some careful business planning I would say 'go for it'. Make sure you have a detailed timescale and cost implications in place as you will need to ensure your on-going profitability at all stages. recruitment is a minefield so, if you have not done it before I would suggest attending a course all about legalities and paperwork requirements which are free at the Inland Revenue.
Also plan and schedule a specific marketing campaign with set timescales for each level whether it is leaflet dropping, advertising, commercial campaigns and be preapred to work hard to meet your targets.
Alternatively, like any it may be that you want to earn XXXXX per montgh and keep a good work-home ratio. Expand to a level that suits you are your situation but the same as above plan it.
Others here may and have said, just do it, dont dither and plan. I remember someone saying 'w/c is not rocket science just go out and knock on doors' but running and growing it does take time and effort. In my huble opinion you should do some groundwork first and then just go for whatever level you decide you want to.
Good luck whatever but should you have any questions, please just ask away. You will get answers that cover both sides of the coin so have an open mind.
Sarah