What's the £6k for? Hope it's not a franchise!!
How much more have you got to, firstly, pay your bills etc whilst it's getting up and running, and secondly, invest more into the business when you find it needs more investment, i.e. better vehicle, more equipment, more advertising, more tools, subscriptions, software, insurance etc etc.
General advice is to ensure you have double the amount you think you'll need to start.
If you're signing any contracts, i.e. lease for premises, equipment leases/rents, franchise agreement, etc., get them checked over by a solicitor so you know what you're getting into it, and more importantly how and when you can get out of them and at what cost.
Don't ignore the book-keeping, accounting and tax side of things - get an accountant to help you set up systems and register for taxes etc, consider whether a limited company would work for you, likewise whether VAT registration is required or voluntarily beneficial.